RDS/ Office 365 E3 activation

Dear TRaG,

Unfortunately, as a forum moderator, I am not able to inspect your servers or tenant to diagnose and fix this directly. My role here is limited to general guidance you can apply from your side. Since this hit multiple users at once on a setup that was working fine until recently, the cause is almost certainly at the host or tenant level rather than in individual profiles. On an RDS Session Host, Microsoft 365 Apps rely on Shared Computer Activation, which needs three things healthy: the setting itself, a valid license per user, and the host being able to reach the licensing service. A break in any one of them takes everyone down together. It would also help to know what changed in the days beforehand. An Office update, a proxy or firewall change, or a license reassignment are the usual culprits when activation stops suddenly across a whole host. Please follow these steps to see if they help:

1.Verify shared computer activation

On each host, check HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Office\ClickToRun\Configuration for SharedComputerLicensing = 1. You can also open Word and check File > Account > About Word, where the second line should read Shared Computer Activation rather than a Product ID.

2.Clear the licensing token cache

If the configuration is correct, stale or corrupt tokens are the most likely cause when everyone on a host fails together. Sign the user out of Office, delete the contents of %localappdata%\Microsoft\Office\Licenses for that profile, then sign back in. Test one user before applying it more widely.

3.Confirm licenses

In the Microsoft 365 admin center, go to Users > Active users, select an affected user, open Licenses and apps, and confirm both that Office 365 E3 is assigned and that Microsoft 365 Apps for enterprise is enabled within it.

4.Check connectivity

From each host, confirm internet access, TLS 1.2 enabled, correct date and time, and that no proxy, firewall or SSL inspection service is blocking the Microsoft 365 licensing endpoints. Office contacts the licensing service periodically to renew each user's token, so a recent network change is worth ruling out before reinstalling anything.

5.Contact support

If it persists across hosts, I recommend that you create a service request with Microsoft Support. A technical support engineer can perform a remote session to investigate the situation, verify the backend configurations, and run any necessary synchronization tools to resolve the problem. If the issue requires further attention, they can escalate it to a specialized team for deeper analysis. For detailed instructions on how to get support, please refer to Get support - Microsoft 365 admin.

I hope this information is helpful. Please follow these steps and let me know how it goes. If you have any questions or need further assistance, please feel free to share them in the comments so I can continue to support you. Thank you for your patience and understanding. I'm looking forward to your reply.

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