Office 365 system requirements changes for Office client connectivity

Published 04-20-2017 08:54 AM 80.8K Views

Editor’s note:

Changes have been made to the Office 365 system requirements. Go here to see the September 6, 2018 update and announcement:


Today on the Office blog, we announced changes to Office 365 system requirements for Office client connectivity and how we will make it easier for enterprises to deploy and manage Office 365 ProPlus. In this post, we are sharing some more detail on what the system requirement changes mean for IT between now and 2020 and why we've decided to make this change.


As technology evolves, system requirements need to change

The new system requirements provide clarity and predictability for client connectivity to Office 365 services. When customers connect to Office 365 with a legacy version of Office, they're not enjoying all that the service has to offer - The IT security and reliability benefits and end user experiences in the apps is limited to the features shipped at a point in time.


When we release new on-premises apps and servers, we use that opportunity to update the system requirements. But there is not yet a common convention on when to update system requirements for a multitenanted cloud service that is always up to date. In absence of that, we are sharing these system requirement changes as early as possible and as part of a larger discussion of the Office 365 ProPlus roadmap for deployment and management capabilities.


As we get closer to 2020, we will share more details about implementation and the user experience for affected desktop clients. The updated Office 365 system requirements for Business Enterprise and Government plans state:


Effective October 13th, 2020, Office 365 will only support client connectivity from subscription clients (Office 365 ProPlus) or Office perpetual clients within mainstream support (Office 2016 and Office 2019). (Please refer to the Microsoft support lifecycle site for Office mainstream support dates.)


Here is a high level summary of  the implications for client connectivity in 2020, depending on how you use Office 365:


 Connectivity to Office 365

Impact of change

Technical implications

Recommended actions

Office 365 ProPlus or Office clients in mainstream support (Office 2016 and Office 2019)

No change

Plan for regular updates to stay within support window

No action required

Office clients outside mainstream support

Client connectivity no longer supported

Office desktop client applications, such as Outlook, OneDrive for Business and Skype for Business clients will not connect to Office 365 services

Upgrade to current version of ProPlus or mainstream Office clients or use browser or mobile apps

browser and mobile apps

No change

No change

No action required

Office desktop clients outside mainstream support not using Office 365

No change

Set your own desktop upgrade timeline, in line with your on-premises server upgrades. When planning to move to Office 365 services, an Office client upgrade will be required

No action required



2020 may sound like a long way away, but your feedback to us has been consistent on the more advanced notice for Office 365 changes, the better. Providing over 3 years advance notice for this change to Office 365 system requirements for client connectivity gives you time to review your long-term desktop strategy, budget and plan for any change to your environment.


For now, the key takeaway is: Office 365 ProPlus is our recommended Office client for Office 365 users. This is the Office client that stays up to date with frequent feature releases and ensures the best service experience.


Here are some resources to help you plan for a ProPlus upgrade:


Thank you!


Valued Contributor
Hi Alistair, how will this change to desktop apps affect feature delivery to web based and mobile versions of the Office apps? How will add-ins be managed? I can understand slowing the cadence to align with the desktop OS, but how does this fly in a mobile first, cloud first world?

@John Wynne, this change doesnt impact the web apps and mobile versions of the Office apps. There is still an option to get monthly desktop updates, but we are changing the 3x a year update channel to be 2x a year to align closer to Windows 10 update model. We are trying to strike the right balance between agile, ship-when-ready updates and enterprise needs of predictability, relieability and advanced notice to validate and prepare. 


In terms of add-in management, my colleagues in the Office ecosystem team are working on some new capabilities to make that easier too.

Occasional Visitor

Maybe I am reading too much into this, but does this mean that the SKUs for Office 365 Business and Office 365 Business Premium will be going away since they do not have ProPlus in them? If they are going away, then will that mean that ALL tenancies will need to be converted to Enterprise level subscriptions by 2020?


@Joshua Chamness - good question. This applies to all of our Office subscription clients - Office 365 ProPlus is our most common system requirements so we often use that as shorthand. Office 365 Business (the office subscription client that is in those SKUs) is subject to the same Office 365 system requirements change in 2020.


The advance notice period is definitely appreciated, but I (and many other businesses I know) are crying out for an Office 365 plan that includes per-device (rather than per-user) licensing for Office Pro Plus (for shared computers with 10+ occasional users) and Exchange Online (for shared mailboxes). The existing 'Shared Computer activation' feature is simply not viable or affordable in an organisation where a user perhaps uses Microsoft Word once a month, or sends an email once a month.


@T Stanley - for such occasional users, perhaps the web apps are a better solution. I'minterested in your thoughts on what features you'd like to see in the web apps that would make it more compelling for your users.





Can we get some clarification on what this means for perpetual versions of Office, such as will there be another release after Office 2016 (prepetual)? And if there is another prepetual version, say an Office 2018, will that continue to be able to connect to O365 services post-2020? The post is unclear what it means for existing, on-prem SA/EA customers with regards to the future of Office desktop outside of using Office 365 ProPlus.


@Trevor, yeah, I'm wondering too, but I think the following lines in a section entitled "implications for client connectivity in 2020" surely means that there must be an Office 2018 (or whatever they want to call it) at that point. Otherwise, it wouldn't make any sense, as there wouldn't be any "regular updates" that would qualify (i.e. Office 2016 would be out of support).


"Office 365 ProPlus or mainstream Office clients...Plan for regular updates to stay within support window."

Occasional Contributor

I must be dense, but the answer above regarding Office 365 Business Premium has me scratching my head. Am I being told that I better plan for something since we use this subscription and the office suite provided by it? If so a lot of extra details need to be provided if we are to "plan".


@Jason Gould Office subscription clients (Office 365 Business, that comes with Office 365 Business Premium and Office 365 ProPlus, which comes with some enterprise plans) are kept up to date with regular feature updates, so they always support full Office 365 connectivity. So - this change in 2020 shouldn't be anything to worry about. 


@Trevor Seward @Brian . - Yes. Microsoft will deliver another version of Office perpetual. There are no details to share on timing at this point, but you should expect this release to follow our typical update cycle. 

Occasional Visitor

We have migrated many of our clients to Microsoft Exchange Online.


Most of those clients are using Office 2010/2013 and not Office 365.


Am I correct in believing that we now have to move those clients to Office 365 Business Premium or ProPlus in order for them to use Exchange Online?

New Contributor

Hi, can you tell me if this applies to Office 365 Education? We currently license the bulk of our users as Office 365 Education for Faculty, but do have the option of Office 365 Education Plus for Faculty, which includes client downloads. Will we need to update everyone to that by 2020? Thanks! Sorry if I'm not understanding the obvious...!

Occasional Visitor

Am I reading into this... In order to use Outlook desktop client, one would be required to use the version provided with ProPlus service? So if this took effect today people currently connecting to O365 services using Office 2010 would no longer meet the requirements and need to use the web interface or upgrade to O365 license that provides an installable version of Outlook.

@Alistair Speirs Will this impact non-Microsoft email clients using POP or IMAP with EXO? Or non-Microsoft clients using ActiveSync/MAPI over HTTP?


@Michael Reed@Jon Heberlin@Trevor Seward let me try and answer both of your questions at once! For context


While these older Office clients won't stop working in 2020, but client connectivity with Office 365 (such as Outlook 2010 connectivity with Office 365) will no longer work and will no longer get security updates. For context, it is good to understand  what is going on with Office 2007 at the moment - once Office 2007 is out of support, we will no longer support it connecting to Office 365 and will retire older protocols, such as RPC/HTTP. Unlike Office 2007, we are still 3+ years out, so not quite ready to talk about which protocols will change and how - but as we get closer, we will publish support articles with more detail, provide targeted admin notification through message center and closely watch our service telemetry to ensure we are minimizing impact to customers. 


What is changing is 2020 is what we consider an older client. Today we make no explicit statement of when a client will stop working other than to say the experience will degrade over time and we will not support anything that is no longer supported. Going forward, we want to get rid of the ambiguity of "degrade over time" andexplicitly define the clients that will work as those in mainstream support (ie, released in the last 5 years) and the Office subscription clients that are always up to date (Office 365 ProPlus or Office 365 Business). 2020 also marks the end of support for Windows 7.


What this means for admins supporting environments with Win7/Office 2010 is you should be taking these end of support dates into account when thinking about your longterm desktop strategy.  We are providing 3 years notice of this change, so you don't have to move those clients immediately, but as you plan your desktop strategy over the next 3 years, you should take this change into account. This may mean planning to deploy Office 365 ProPlus (or Office 365 Business), using Outlook on the web or deploying the next perpetual Office client release which I referenced above.


If Office 365 ProPlus is your choice, FastTrack has engineering resources to give you guidance, best practices and help you get up and running, at no additional cost.


@MCLS admin Hi, this change impacts Office 365 Business, Education and Government plans in 2020. You don't have to use an Office client to use Office 365 (and we find that many educational institutions use the web apps via the browser), but if you do, we recommend the Office 365 ProPlus client that come with some Office 365 plans. You will also have the option of the next perpetual Office client release , as I mentioned above, but we dont have any timing or details to share on that yet. 

Occasional Visitor

How will this change impact non-profit plans, especially access to one drive and skype? Many non profits will allow their regular volunteera to use their own office apps and then save/share work via one drive as this saves considerable costs to the business. Similarly Skype for Business is currently downloadable as a desktop app without needing office installed... will this no longer continue? 

New Contributor

@Amit LathiaI'm curious as well.  I'm also not sure I follow the line that we must be perpetual, but mainstream support is 5 years (Which should still include  Office 2016 ProPlus VL.

Regular Visitor

How will this affect someone connecting to Office 365 Business Essentials when using this edition of Office 365 desktop? 


Will it work or will they need to transition to Office 365 ProPlus directly from Office 365 for Business?



Occasional Visitor

Does Office 365 Services here mean ALL Office 365 branded services? I am asking specifically about Exchange Online Protection, DLP & Exchange Online Archving for Exchange Server - the "Services" included in the ECAL suite, that do appear to end users in Outlook in the form of policy tips etc. Will these services also only work with Office perpetual client's in mainstream support come 2020?


Also, will this impact something like the Office 2013 version of the Office 365 Pro Plus client? I know it is no longer supported, but it still connects to Office 365 services no problem.

Trusted Contributor

Maybe you could find of interest the Paul Thurrott's opinion:

Occasional Visitor

Hi Alistair,

Thank you for the information. We just deployed Skype for Business clients for some of our users that are currently on Office 2010 (with the Skype Meeting Add-in for Microsoft Office 2016 installed). The company I work for will most likely want to opt for what Microsoft now calls "Office perpetual". So I am curious what our upgrade path is going to be for these users starting on October 13, 2020?


Thanks in advance for any information!


@Amit Lathia - non-profit plans are subject to the same system requirements above. 


Hi @Nathan Parker - yes, Office 365 Business is fine - and it will stay up to date and support the latest Office 365 functionality. Office 365 Business Essentials plan doesnt include an Office subscription, but that does not preclude a user with another Office client from connecting to it. 





Hi @Justin Stenger - best way to think of it is as we retire/deprecate old protocols and APIs from Office 365, the older clients that depend on these connectivity options won't be able to connect. As we get closer to 2020, we will provide more specificity on the implementation detail. For things like EOP and EOA the service descriptions outline the requirements and minimum versions required -






Thanks for sharing @Salvatore Biscari - its a pretty good summary of these changes (although the title and image is a little theatrical for my tastes :)).


Hi @James Wilber - Office Professional Plus 2016 (the current perpetual release) comes with Skype for Business, so as your users are upgraded to a newer version of Office you should not expect to have to deploy (and patch) the Skype for business client separately. 






Regular Visitor

@Alistair Speirs Thanks for the info. The version of Office I mentioned was Office 365 University. That's the version connecting to Office 365 Business Essentials. To confirm, Office 365 University (the version at the link above) will be able to continue connecting to Office 365 Business Essential services after the date mentioned by Microsoft, correct?

Occasional Contributor

Hi guys,


Interested in how this change will affect non-Microsoft client access to Office 365 Exchange Online.  We have an enterprise environment with a large Linux and Mac community and some business workflows that utilise non-Microsoft mail clients, and plain-text email utilisation with client automation with non-Microsoft email clients is prevalent. 


With respect to:

“Important changes to system requirements: Effective October 13th, 2020, Office 365 will only allow Office client connectivity from subscription clients (Office 365 ProPlus), or Office perpetual clients within mainstream support, to connect to Office 365 services. Please click here to learn more”


  1. Does this mean that after 13/10/2020 non Microsoft email clients that use standard email protocols that Office 365 Exchange Online currently supports (e.g. IMAP and POP3) will no-longer be able to access email via our Office 365 tenant?
  2. Does this mean, for example, that access to Office 365 Exchange Online email via Thunderbird, mutt, git send email, Apple Mail will not be supported?
  3. Will Microsoft be releasing Outlook clients for Linux, or if not how will Linux clients access Office 365 Exchange Online email?


Kind regards,




Not applicable

The announcement talks about Office 2016 perpetual use licensed apps not working, but it does not mention Office 2016 Pro Plus that is bought via MVLS subscriptions (like most enterprises and govt organizations).


Will those stop working when they exit mainstream support in October 2020? If so, the announcement needs to be updated to include that more clearly. And if not, call out that those will still work.

Occasional Contributor

@Alistair Speirs very good information, thanks for the heads up!


You should really include your "technical" comments made in the post ‎21-04-2017 10:31 PM (sorry I don't know how to directly link to posts here) about protocols being deprecated. This explains a lot the reasoning behind this change and I believe it is a very good reasoning - why not share it more publically than in a comment.

Frequent Visitor

Our school has Office 2010/2013 Clients installed with exception of Outlook as we dont want that on machines.  We also have EES licences for Office 2016 client. The school has Office 365 A1 Plus for faculty.


Do these changes mean that I have to uninstall all clients and download to each machine the Office 365 A1 Plus version during this timespan to 2020,


From various mailouts, websites it seems that no local client except the one from Office 365 will be acceptable

Occasional Visitor

Sorry but this explanation is like a lot of Microsoft "explanations".


Lazy and ambigious.


---- Office Proplus is our most popular option so we use it for shorthand. Really shorthand for what? Does everyone in the world know that?

---- "mainstream Office clients" what exactly does this phrase cover?


A grid of your products detailing the actual product name that everyone uses would be good for every level of your price plan set


Along the lines


Small Business

  •   Business Essential - Yes or no  
  •   Business - Yes or No
  •   Business Premium - Yes or no
  •   Exchange Online - Yes or No
  •   Skype for Business Plan 1 and Plan 2
  •   One Drive for Busines Plan 1 and Plan 2
  •  etc..
  •  etc..


  •   Pro Plus - well obviously Yes
  •   E set of plans - Yes or No


  OEM Desktop licenses

  •       2007 - Yes or No
  •       2010 - Yes or No
  •       2013 - Yes or No
  •       2016 - Yes or No

Third Party Clients  

  •    Apple Mail
  •   Thunderbird
  •   Windows 10 Desktop Mail there's an interesting question
  •   Android Phones
  •  IOS Phones



(something else out of the Mad Hatters tea party that is Microsoft Corporate strategy - Promote Outlook as the email client, it can have connections to       every major other email provider and on-premise solutions.......except for Microsoft's own flagship mail system Exchange Online.)


Does this change also apply to Hotmail/Live as they appear to have been absorbed into the Exchange system?


Volume Licencing agreement?


Government, Non Profit and Education agreements?


Another Alice in Wonderland announcment, Non profits couldn't purchase CSP licences until a couple of months ago and had to go through the Volume Licensing route for say 5 years agreement, so now they have to go through a plan to migrate to CSP.





Occasional Visitor

Hello,  We are a small business using Business Essentials and Business Premium.  Does this change mean that all our licenses need to become Office 365 Pro-Plus or will our Premium and Essentials licenses keep working as is?  We are using Office 2016 as downloaded from Office 365.  What does Mainstream Support entail regarding contract time and costs per user?

New Contributor

It's absurd that we can't get a clear answer on how this will affect email/ActiveSync. Is Microsoft seriously saying that Outlook 2016 will no longer work with Exchange Online which support ActiveSync? If that's true how does that affect every other app that uses ActiveSync? Will my employee's company issued iPhones no longer get email through the native email app? How about my android phone? Will that not work?


If it will work on all those devices but not Outlook 2016 is Microsoft going to specifically block Outlook 2016 clients from using ActiveSync but still allow everyone else to use it? Or are they changing the ActiveSync protocol in such a drastic way that all these apps will have to be updated and as a side effect Outlook 2016 will no longer work?

Hi everyone. Thanks for all the feedback on this topic. The good news is that we will now support Office 2016 connections with the Office 365 services through October 2023. I'd encourage you to read this full article on some of the improvements and changes to desktop supportability:
Senior Member

"Office desktop client applications, such as Outlook, OneDrive for Business and Skype for Business clients will not connect to Office 365 services".   Does it mean (1) the older clients cannot connect to Office 365 at all as Office 365 will detects the older versions of client and refuses to connect or (2) older clients can still connect but it is just not supported.     It seems to be the formal case but we just want to be 100% certain, thanks!

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