Forum Discussion
Activation failed
I have been running MS 365 on my Mac laptop for years with no issue. Suddenly I cannot save an Excel file. I saw the activation button, but activation failed with the code OxO....unknown cause. I can...
Hi JonHunt,
Error code 0x0 is a bit unusual because it generally indicates the activation process didn't return a specific error, making it more of a generic activation failure than a licensing issue.
A few things I'd try:
- Sign out and back into Microsoft 365 from any Office application (Excel > Account or Help > Sign Out), then restart Excel.
- Open the Microsoft AutoUpdate app and make sure both Office and AutoUpdate are fully up to date.
- Confirm your Mac's date, time, and time zone are set automatically, as incorrect system time can interfere with license validation.
- If you're signed into multiple Microsoft accounts (personal, work, or school), make sure Excel is using the account that owns the active Microsoft 365 subscription.
- If the issue started after an update, try removing the Office license credentials from macOS Keychain Access (look for Microsoft Office or ADAL/MSAL entries), then sign in again to refresh the activation token.
Since you mentioned your desktop still shows an active subscription, the subscription itself is probably fine. This sounds more like a local activation cache or credential issue on the Mac.