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I have purchased 365 again but it wont activate and I have tried all the self help articles called you twice, signed in 47 times and nothing works. I need this to run as I cant do anything without it. Can someone please help. NOT Ai and not more self help rubbish
A family of Microsoft word processing software products for creating web, email, and print documents.
What version is your macOS? Office no longer works with many older Macs.
Running MacOS Catalina version 10.15.8 if this is the issue how do I go about getting a refund for the office 365 package I have paid for out till 2028?
Which macOS version are you using?
Since there was a licensing update on July 13, 2026, this could be related to your issue depending on your macOS version.
That may be it as It was ok last week but turned to custard this week.
Running MacOS Catalina version 10.15.8 if this is the issue how do I go about getting a refund for the office 365 package I have paid for out till 2028?
Is there a reason you marked the answer as not helpful? Did I miss something? If so, please let me know.
Since you're on macOS Catalina (10.15.8), which is even older than Big Sur, this is the same July 13, 2026 certificate issue we discussed, your Mac falls well below the macOS 12 (Monterey) minimum now required.
That said, your Microsoft 365 subscription itself is still fully valid, this is a limitation of the desktop app on this specific old Mac, not something wrong with what you paid for. You can keep using it in the meantime through Word, Excel, and PowerPoint online for free at microsoft365.com, or on another device that meets the requirement.
As this is a public community forum, we do not have access to purchase data or information. You will need to contact Microsoft support.
https://support.microsoft.com/contactus
Type "Billing" as the keyword > Click the "Contact Support" button.
Choose "Microsoft 365" > "Manage my subscription".
You’ll then see the option to chat with a Microsoft support agent who has access to your account to help review the issue.
sorry no it was helpful thank you not sure why it did that sorry.
Don't worry, I just asked to make sure I didn't miss anything.
If you have any further questions, I’ll be happy to help.
If you wish, you can click the "Accept answer" button; this will help other users who encounter this topic with the same problem.
Im trying to install the older 16.66 version so it works, I will keep you posted, thanks for your help so far.
I'm sorry, but it's likely that 16.66 won't actually fix this. Since no build released for Catalina, or any macOS below Monterey, ever got the update needed for this, you'll probably end up in that same reduced functionality mode.
I just installed the older 16.66 version and it is still failing to update. I have turned off auto updated and shows to be running 16.66.1. ???
This is expected behavior. The application installs and runs normally on Catalina but cannot be fully activated, as macOS 12 or later is required. Installing an earlier version does not resolve this issue.
So the question is how do i keep using microsoft on my old Mac? I have tried all sorts so far to no avail.
The honest answer is you can't keep using the Microsoft 365 desktop apps on this Mac since it's below the required macOS version.
Your option is to use Microsoft 365 on the web instead, through microsoft365.com in any browser.
Do you have any further questions?
Is there anything else I can help you?
No all good thanks, I managed to get the online system working but is a bit of a pain. I cant seem to find how to delete files from the online system however?
Glad the online version is working. To delete files there:
Go to onedrive.live.com and sign in with the same account
Find the file you want to delete
Right-click it (or select it and click the three dots at the top) and choose Delete
If you're inside Word, Excel, or PowerPoint online and want to delete the file you currently have open, click File at the top, then Manage in that menu should take you to OneDrive where you can delete it from there.
If you have any further questions, I'll be happy to help.
If you wish, you can click the "Accept answer" button on the answer that helped you; this will help other users who encounter this topic with the same problem.
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I am experiencing the same issue running macOS Tahoe 26.5.2 on a 2020 iMac. Each time I attempt to use Excel I have to Activate my account and then I get an 'Unable to Activate Office' message. I have a personal account with Microsoft Office 365 as opposed to a school or business account. Any suggestions on how to get it working again would be greatly appreciated. I have already been down the AI rabbit-hole with no success
Thank you - problem resolved! Thought I had already been through all the steps advised, but apparently not. Great to have it working again.
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I just opened Excel today had this issues. Updated to MacOs 26.6 the reinstalled Microsoft 365 and all MS apps were able to be activated. They could have told us this in 2 sentences.