Adding 365 to newly built PC - cannot activate

Question

I have an annual subscription to 365 and cannot activate it. It renews June 27th. I have it on only two other devices but cannot activate.

My original product key is H***4 and will no longer work.

When I try to use it or log in i get the following:

Correlation Id: a7412c59-138c-4673-a5fb-2f895918b558Timestamp: 2025-02-24T20:29:28.000ZDPTI: 9a8d03520ef31f5b795ca99d910665f7cad41777b8d71994f358cd239d136443Error Tag: 7q6caError Code: 2147483661

Answer 1

To install Office on a new computer, sign in to https://account.microsoft.com/services and install from the account.

You can't use the product key after the initial install.

Answer 2

Dear Dan Talbot

Welcome to Microsoft Community.

We understand that you encountered an error when activating Microsoft 365.

According to your description, you shared your key information with us. Since the Microsoft forum is a public discussion platform, we will hide your personal information for your information security.

We see that you use Microsoft 365 subscription, and you can indeed activate and use the program on multiple devices, but we see that the error message displayed when you log in is 7q6ca, and we need to confirm with you:

You said that you use the product on two devices, so are you unable to log in and activate the product on all devices? Or is it that only one device cannot log in and use it?

About this error, I need to explain to you:

We have also received feedback from other users about this error and problem. This is a hot issue reported by users around the world recently. We initially assessed that it may be due to compatibility issues between system configuration files and Office updates.

Some users said that they could alleviate the problem by trying to clear the cache or create a new local system account to check the system's detection information. You can help with the operation:

I. Clear the corresponding login credentials for confirmation

1. Press Windows+R to open the run box, copy and paste the following path, back up all the folders in this path and then delete them. %localappdata%/Microsoft/OneAuth %localappdata%/Microsoft/IdentityCache
2. Press Windows+R, enter regedit, click OK, open the registry, find the following registry subkey, right-click Identity, and delete it. HKEY_CURRENT_USER\SOFTWARE\Microsoft\Office\16.0\Common\Identity

Disclaimer: Generally, modifying registry subkeys or work group is intended for advanced users, administrators, and IT Professionals. It can help fix some problems, however, serious problems might occur if you modify the registry incorrectly. Therefore, make sure that you follow these steps carefully. For further protection, back up the registry before you modify it. Then, you can restore the registry if a problem occurs. For more information about how to back up and restore the registry, click here to view the article.

II. Create a new local system account:

You can try to create a new local administrator account for the system, use the new administrator account to log in to the system and log in to your OneDrive to confirm whether it can be used normally.

You can refer to the detailed steps in the following link to create a new local account:

Manage User Accounts in Windows - Microsoft Support

We also look forward to you sharing the results of your operations with us.

Please understand that our initial response may not always solve your problem immediately. However, we will also rely on your subsequent help and more detailed information so that we can find a solution together.

Best Regards, 

Zenobia.Z | Microsoft Community Support Specialist