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We've been doing Office 365 migrations for years now, so we've probably seen just about any scenario you can imagine. This list was cultivated over many projects and many customers of different sizes in order to help our staff understand the needs of our clients and identify potential risks, obstacles, or opportunities that might arise during or after the Office 365 migration. Think of this page like a "reverse FAQ".

We encourage anyone considering an Office 365 migration project to read through this list and try to answer as-best-as-possible those questions raised here. Doing so will ultimately lead to a better RFP and better proposals from us and our competitors alike. Ultimately, anyone offering services or support for Office 365 should be asking their customers these questions at a minimum. If that's not the case, best to keep looking.

Even if you're thinking of going it alone and doing all the technical work yourself, please use this list for your own planning purposes to ensure there isn't something important that you might be overlooking.

And, don't worry if you don't know all the answers; that's what we're here for, and ensuring these things are addressed at the proper time is part of our service to you.

Basic Subscription Information

This section covers information about the Office 365 subscription itself and how it will be configured.

How many people in your organization will need Office 365 accounts?

This is just a basic head-count of your users. During the process of signing up for Office 365, you'll need to make some decisions about what type of license to give each user based on how they'll use Office 365, and that's something we can help you with.

How many Office 365 Tenants (Subscriptions) are you planning to use?

For most organizations the answer will be 1. However, some orgs will have international operations that suggest creating multiple subscriptions hosted in different geographic areas, and others may wish to create additional tenants for development or testing of advanced features.

What are your preferences for a "tenant ID" (pick 3)?

Every Office 365 subscription must be given a unique name. Once you choose a tenant name, it can never be changed, It's very important to pick a name you'll want to use indefinitely. While we're not quite at the point of having to choose spam-bot sounding names like "mycompany54371", many short names have already been taken. Avoid names with "dev" or "test" in them, unless the subscription will never be used for purposes other than development or testing. Likewise, since the tenant ID will appear in account names and URLs for sites like SharePoint, make sure you pick something short and representative of your organization. As a best practice, we recommend you pick 2 or 3 possible names, so we have some alternatives in case your first choice is taken.

How many DNS domains (e.g. "") do you have? What are they?

Again here usually the answer is 1, but there are cases where you may have multiple domain names.

Where did you register your DNS name(s)?

Many times the answer will be "GoDaddy", "", or "Easy DNS" but there are literally hundreds if not thousands of DNS registrars, all with different systems and capabilities. (Some registrars don't support advanced records like SRV and TXT, which may require you to migrate to a new registrar.) Make sure you know which one you used and have your credentials handy. You can use WHOIS to find out if you don't know the answer.

What Office 365 Products / Services will you use now or in the near future?

  • Outlook / Word / Excel / PowerPoint / OneNote
  • Access / Visio / Project
  • SharePoint Online
  • OneDrive for Business
  • Skype for Business
  • Power BI
  • Project Online
  • CRM Online
  • Yammer

Project / Staff Information

Here we address some of the more touchy-feely areas of how an Office 365 migration project can be handled.

What's your communication plan?

If you're just 3 people, your communication plan will probably involve everyone getting together around the table, crossing your fingers, and then pulling the trigger. If you have more people working with you, you'll probably want to plan for keeping everybody in the loop as changes are made. A communication plan describes how you'll keep people informed, especially under circumstances where sending an email might not be an option.

Who will handle IT support for your company? Where are line of responsibility drawn? What are your contingency plans?

If you have an IT department, then you probably already have support structure in place? If you're a smaller organization, then you will want to think about who will support you not only for Office 365 related questions but also for things like general internet connectivity and basic desktop computer usage. For example, do you have an office admin, freelance IT person, or managed services provider who normally handles these things for you? If so, it will help us to understand who they are, what their role is going to be in the future, and plans are in place in the case that they're not available anymore. If not, we'll need to discuss how you're going to handle the higher need for support that's typical with transitions like Office 365 migration.

What project approach works best for you?

Are you a fast-moving business full of busy people who need a full service implementation, or are you a boot-strapping start up that needs to watch every penny? Maybe you have an IT person in house and want them to participate in the migration process so they can learn and support you down the road? Telling us the approach you prefer helps us to propose the migration plan that works best for you. We have full-service, joint effort, and assisted self-service options to fit every budget.

What level of training do you need?

Depending on how you plan to use Office 365, you might be able to get by with a learn-as-you go approach. This is fine if you'll mostly use Word, Excel, PowerPoint, OneNote, Outlook, Skype for Business, and Yammer. If you intend to make use more advanced capabilities like OneDrive for Business, SharePoint, Project, CRM, or Power BI then you might need some end-user, power user, or administrator training. We have a variety of different options here including instructor led classroom, webinar, train-the-trainer, and 1:1 sessions.

Fleet Information

This section covers information about your computing devices and peripherals that can affect how we go about helping you migrate to Office 365.

How many workstations (PCs, laptops, MS Surface or similar Windows tablets) do you have?

A basic count of workstations is important because it determines how much work will need to be done to configure Office software and set up connectivity to e-mail and other services. Some people will have more than one workstation, and sometimes there are shared workstations around the office (server closet, copy room / postage meter, reception desk, warehouse floor, etc.) so make sure you've accounted for all of them.

What operating system and version is running on each workstation?

Some older OS don't support Office 365. This is especially important if you plan on installing Office yourself, because the instructions we'll provide you will be different on various versions of Windows. Likewise, if you're using any Apple PCs or MacBooks with OSX it will be crucial to identify this as early as possible, because these software and procedures are so very different from their Windows counterparts.

Do you have any version of Microsoft Office currently installed? If so, on how many PCs?

To avoid technical problems down the road, we recommend as a best practice to uninstall any existing version of Office from your computer before installing Office 365. If you want to preserve license keys for older versions of the product that you've purchased, and you don't have those on file, there are special steps we can help you take to recover the license keys from the PC itself. Likewise, if you're currently using Outlook to connect to e-mail, there will be special migration procedures we follow to ensure that you can use your e-mail with minimal interruption during the transition.

How many mobiles (phones, non-Windows tablets) do you have? What kinds Android, iPad) and how big are the screens?

If using mobiles / phones is a part of your workplace, they'll need to be configured to connect just like desktops do. It's also important to note that many devices with smaller screens don't even use a license when you install Office 365, but some tablets with larger screens do.

Will your users also be setting up personal devices / home computers? If so, how many?

Many Office 365 licenses give you access to use Microsoft Office on multiple computers. One benefit to this is that is enables BYOD (bring your own device), by ensuring that your users will have access to the same tools they use at work when using their personal machines - in the office or at home. As part of the migration process, you need to decide if you will help users configure personal devices, if they'll have support or be on their own when they do this, or if you want to set a policy that personal devices aren't allowed.

Network Configuration Information

This section covers information about how your office computer network is configured and managed.

Not counting home offices, how many physical branch locations do you have? Where are they?

Understanding how many locations you have helps us to predict how your switch from a traditional to cloud computer model might affect your bandwidth usage. For example, while downloading files from Microsoft will use more bandwidth than if they are on your local network, users connecting from home or branch offices will not be using bandwidth to connect to the main branch for access to files.

Who provides the internet access at each branch? How much bandwidth?

When planning a move to Office 365 it's a good idea to make sure your internet connections can handle the change in network usage. This is also an excellent time to review the plan provided by your ISP. If you've been on the same plan for a very long time, chances are good that you're overpaying for bandwidth and may have other options available - even if you don't change your ISP.

Are you using land lines, Wi-Fi, or both? What Wi-Fi router or network switches do you use? Are they b/g/n or something else?

Most companies are using Wi-Fi in some form or another. Over time, we've observed that issues with outdated, misconfigured, or faulty wireless adapters or network switches are often the root cause of connectivity problems for Office 365 users. Planning an Office 365 roll-out is a good time to test your equipment to make sure you've identified any faulty network ports, bad cables, or issues like overcrowded radio spectrum or trouble spots that can lead poor Wi-Fi reception.

Are you currently using a VPN connection or appliance to get remote access to files or services at the office? If so, which one?

If you use a VPN appliance or service to connect when at home or on the road, most likely we'll also be using this to connect to your network so we can support you remotely. Typical VPN solutions include Cisco ASA/AnyConnect, VMWare, SonicWall, Microsoft, OpenVPN, and others. Note that if you don't have a VPN appliance, today there are many good So-Ho VPN solutions bundled into mid-grade business-class Wi-Fi firewall appliances.

Are you using a Windows Terminal Server for remote connectivity?

We ask this question because there is a good chance that switch to Office 365 will give you an opportunity to shut down that server, saving money on licensing, hardware, electricity/cooling, and maintenance costs.

Login / Authentication Information

This section covers information about how you sign on to your internal network and how you will sign on to Office 365.

Do you use an Active Directory Domain / Windows Domain Controller?

If you're using Active Directory, chances are that you will still do this after switching to Office 365, because AD helps you secure and control your local computer and network resources. However, you will have some choices to make regarding whether and how to connect local accounts with Office 365.

Do you want to Implement User/Password Synchronization?

If you have more than 50 employees and at least one IT person on your staff, then you may benefit from using Active Directory Sync to connect usernames and passwords in Office 365 with those inside your organization. AD Sync technology is complex and not suitable for everybody, so if you have a smaller organization but still want user/password synchronization, we can help you evaluate Windows Server Essentials as a simpler and more manageable alternative.

Do you want to Implement Single Sign-on?

If you're considering username/password sync, why not go to the next level and implement SSO so that user's won't be asked to type a password at all when logging into their Windows desktops? This requires running an internet accessible Windows server with IIS, AD Sync, and ADFS on your own network, so it isn't suitable for everyone, but many mid-size or larger organizations find it to be an advantageous and time-saving feature of Office 365.

Do you have more than one AD Domain in your AD Forest? If so, how many?

This won't apply to most organizations that have only one domain, but large companies - and some smaller ones in rare cases - will have multiple domains. Because of the way that Office 365 integrates with these kinds of environments, its helpful to know if this is the case.

Do you currently use a Single Sign-on solution?

Again, this won't apply in most cases, but some organizations will already have something like ADFS or SiteMinder in place to provide SSO for a variety of enterprise web applications. If you have something like this, letting us know helps us plan a solution that integrates with you already have.

E-mail Information

Often E-mail is one of the first things we'll implement for a switch to Office 365. This section collects some information that will help us with that process.

What e-mail system or server are you using now?

Some organizations will have their own Microsoft Exchange or Lotus e-mail server. Others use services like G-mail or some other POP/IMAP compatible e-mail system. If you own your server, we'll need to know the exact version you're running. If you use a service, we'll need to know the name of the e-mail provider and we can figure the rest out from there.

Are all your existing e-mails in the same system or are they spread out?

Many companies will have all their e-mail on the same service - like G-mail, your own server, or your ISP's e-mail system. Others may be using personal accounts on many different systems. It's important for us to know this, because it will change the way we approach connecting to those accounts.

How many people will be moving e-mail from another account/system?

This is often the same as the number of users in Office 365, but sometimes you'll have new users coming on board at the same time who won't need e-mail to be migrated. The answer affects the cost of software service that we use to perform the migration, the time that it will take to migrate, and possibly what approach we take to the cutover.

What email aliases do you typically use? Which naming format is the primary?

Many organizations prefer to have things set up so people can receive mail at several addresses. An e-mail alias is an alternative name, like "tcarpe" vs "thomas.carpe" or you might have multiple domains like "" vs "". It's also important to understand which address will be the default, which is what the recipient of your email sees in the reply-to field. These need to be identified and cataloged as part of the process of migrating user's email accounts, and there's also an opportunity during the inventory process to make adjustments and improvements.

How much space in GB is used by all mailboxes combined?

First things first, we'll want to make sure we understand the amount of data that needs to be moved to migrate mailboxes. Knowing this figure factors into migration time estimates.

Does the above figure include mailboxes for people who are no longer with the company and if so, how many mailboxes / GB for those?

If you have a lot of mailboxes for users who are no longer around, you have a few choices when deciding what to do with the data. You can choose to export the data to PST files and back it up with other archival information that won't be copied to Office 365, you can use one or more shared mailboxes to house the data where it can be easily accessed, or for larger amounts of mail and ongoing needs you can use Exchange Archiving service in Office 365.

What's the typical size in GB of a user's mailbox? What's the largest?

This is even better if you can share a breakdown by individual user. If you don't have it handy we can gather this kind of detailed information shortly after starting the migration process. The largest mailbox we've ever seen was 45GB, and it's not too unusual for a small handful of people in any organization to have mailboxes over 20GB. The reason it's helpful has to do with determining which mailboxes should be migrated first, and which users might take longer than others or have more issues with attachments. It might also factor into purchasing additional storage, though we've found Office 365 e-mail storage limits to be quite generous.

Do you have in place any on-premise or cloud based e-mail archiving solution?

Knowing what you use now to back up e-mail will help us determine if your current strategy will work after moving to Office 365. If not, we have partners offering solutions to move your email archives to a new system as you make the switch.

Are all email users on a single DNS domain? If not, how many domains are in use?

Sometimes we see organizations where every user has a couple of different e-mail domains. Other groups will have more than one domain, but assign certain users to one and certain users to others. For example, you might have "" and "" with different people assigned by location. Knowing this helps us determine if any special steps need to be taken to configure migration or Office 365 settings.

How many aliases, distribution groups, or group mailboxes do you have? What are their names? Who needs access to each?

We all have these, stuff like "" that goes to several people or is a separate mailbox that several employees share. As you move into Office 365, there's an opportunity to think about how you want these to work on the new platform. Will you use distribution lists where everyone has a separate copy of the email, or shared mailboxes where everyone can access the shared mail like it’s a sub-folder of their own mailbox. Shared mailboxes are also nice because they don't count as "users" for licensing purposes.

Are you using Google Group Calendars?

We ask this question because group calendars in Google require special handing to ensure that the migration process is done in a way where their date is preserved as it moves to Office 365. This process takes a bit of work and is just a bit more complex than moving a regular mailbox, but still quite achievable.

Do you have any services, appliances, or equipment in your office that send e-mails?

Often, companies will have printer/scanner/fax, servers, or other equipment that send e-mail notifications using SMTP. These systems are older and frequently they don't support the type of encrypted connections which are becoming increasingly common and are required by Office 365. If you have such needs, there are software and cloud services that address this challenge. It's very important that we identify this ASAP because they take careful planning to avoid any interruption of normal operations.

Do you rely in DMARC or DKIM to provide additional e-mail security?

If you have never heard of these, chances are the answer is no. However, if you're an organization that has a recognizable and respected name and e-mail domain, then chances are you rely on these technologies to prevent spammers, scammers, and phishers from using your name and reputation to deliver unwanted and potentially dangerous emails to the unsuspecting public. Office 365 provides limited-but-improving support for DMARC and DKIM configurations, and other vendors such as McAfee help to pick up where they leave off.

Do you need secure message delivery via e-mail?

Most people do not think about the fact that e-mail on the internet is was designed as an open system where the messages can be read in plain text. This is sort of like taping your letter to the outside of the envelope. Recent security events are starting to change the way we think about e-mail, and future implementations will probably be much more secure. In the meantime, there are solutions in Office 365 that can be leveraged for sending data in a secure way. If your business requires you to transmit financial, personal, or other such sensitive information on a regular basis, please let us know.

What MX cut-over strategy do you prefer?

There are a couple of different choices about how to make the transition to Office 365 mailboxes. In small organizations (50 people or less) an all-or-nothing style cutover migration is probably the way to go. You can choose early cut-over or late cut-over.

In early cut-over, mail will start showing up in Office 365 right away, but people may need to use the Outlook Web App to check mail using their web browser while we help each person get mail accounts and Outlook set up on their PCs, and their old mail might take a while to move over to the new system (though they can still connect to the old account if needed).

In late cut-over, people continue to get their mail in the old account while we migrate the mail to Office 365. During the migration, users can connect to OWA to see their new old mail as it gets copied over, to send mail, and to set up their e-mail access in Outlook and phones. Once the bulk of all the users' mail has been copied and their new account connectivity is tested, we perform a delta migration of only the most recently received mail. Users then switch over to the new accounts on the same say that new mail starts showing up in Office 365 instead of the old mail system. Finally, we perform a final delta-pass of the old accounts to ensure that any straggling e-mails get picked up and moved to Office 365.

For bigger organizations, there are many other approaches including hybrid migrations, where we may be copying or syncing mail in two systems for a longer period of time. These situations are much more sophisticated and will require a lot more effort, but if you have more than 100 users in your organization, such an approach might be necessary. In such a case we'll help you weight the costs and benefits and make that decision.

File Migration Information

If you have files on local machines, servers, or other cloud systems, tell us about those and your plans for them regarding Office 365. File migration can be quite a complex issue, and it can be costly in some cases. Here are some basic things you should gather that can help start the process.

Where do your files live?

Are they on people's personal computers, a file server, or something like Dropbox or Google Drive? Do you have files stored in

How much data is there in each location?

You need to inventory the size of each folder or file share. Most software that can migrate files will come at a cost based on the number of GB that you want to migrate. At the very least, knowing the sizes will help determine the level of effort involved and amount of extra cloud storage you might need.

How are files secured and accessed?

If files need to be moved, how will they be accessed? Are they stored on file shared with Windows security, and if so are there security settings on certain files or folders that might prevent them from being copied to the cloud?

What are your file characteristics?

It's important to know not just how big your total file collection is, but also what types of files and average/minimum/maximum/mode sizes for each type. For example, if you have a bunch of ISOs, executable programs, or huge video files those might not be a good fit for the cloud. When we do planning engagements for our larger migrations, we use tools that help to figure this out, but if you're a smaller organization you may be able to do your own storage inventory.

How do you use the files?

For example, if there are servers or specific business applications (e.g. QuickBooks) that need the files, then they may have to stay where they are - or be synced locally from the cloud. If files are rarely used or needed, then archiving may be the best option. If they're used by people every day, then maybe they should go to the cloud first. Also, are they shared with people outside the organization?  Consider if they will be accessed from mobile devices, consumed in a workflow, frequently read, change rate of existing data, new data generation.

How are your file systems organized?

You may have a very thorough and consistent file and folder structure, or things might be a total mess, or maybe it's somewhere in-between. In every case, switching to Office 365 provides you an opportunity to improve how things are organized. Going beyond a basic description of where things stand, you should try to describe in detail you your filing system works and how it varies by network drive or department. These things will not only help determine the correct migration approach, but also help to prioritize so you get the biggest benefit early on.

Where are files going to live?

It's important to plan for where your files are going to end up once they get to Office 365. If you're thinking is that everyone in the company is going to copy their entire C: drive up to OneDrive for Business - including the big boss who has every file the company ever created since the 90s - then you probably need to rethink your approach. While OD4B is a great offering, Office 365 has better options for collaboration and file organization like SharePoint Online, and those large files archives should probably be addressed by a cloud backup solution.  Are there identified sources for the migration which are categorized or grouped such that would map from a file server to a specific SharePoint site, library, One Drive for Business (for example by location, department data, etc.)?

Will you move everything or just some files?

Usually when we move from one house to another, it's not unusual to make a decision to leave certain things behind. Likewise, when you move to the cloud you probably don't need every file you have on your local drives. Of course, if stuff you need and stuff you don't is all mixed up, there'll be some effort involved in organizing things too.  Consider the organization and storage needs for files which are not being migrated.  Be sure you have considered scaling of existing infrastructure to minimize storage and server license costs.

How soon must files be migrated?

It is unlikely that you'll be able to move everything over prior to opening the doors for new users in Office 365. Based on how many files you have, make a schedule, and set priorities. Based on the urgency and whether you have months, weeks, or days, we can adjust plans accordingly.   In order to fully understand how to determine deadlines and priorities, it is often necessary to take in consideration other factors that will influence the schedule such as file servers/storage license expiration, decommissioning of hardware (server or storage), scheduled infrastructure changes such as migration to or from  physical or virtual servers, etc.

What about access while migration is in progress?

There will likely be cases where you need to make sure that users always know where the correct, latest-and-greatest version of a file is stored. Office 365 solves that challenge in the long term, but moving into it might cause confusion as different file collections move at different times. Also, maybe you have certain files that are so important that you can't be without them for even a few hours. Good planning and communication will go a long way to mitigate these challenges.

Who will do the heavy lifting?

While we can provide a lot of value in helping you organize and move your files, not every company has the means to afford a full-service approach to file migration. Sometimes the most cost effective approach is to put tools and training into the hands of key people in your organization that let you manage file migrations yourself. Often times even in these cases, we'll need to work hand-in-hand to help you plan your new file management strategy in Office 365 and keep momentum driving things in the right direction.