I cannot open Microsoft Office apps like Word, Excel, or PowerPoint on my mac.

Microsoft cannot initiate a phone call from this Q&A post, but you can request assisted support through Microsoft’s official support page and, where available, select a callback or use the phone number listed for your country/region.^1^

Request Microsoft support

1. Open Contact Microsoft customer support.^1^
2. Select Personal account if this is your own Microsoft 365 subscription, or Work account if it belongs to an employer or school.
3. Under Microsoft technical support, select Get help.
4. Enter:
   Office for Mac keeps signing in with an old account after reinstalling. I need activation and account support.
5. Continue to Contact Support and select the available chat, callback, or telephone option. Availability depends on the product and country/region.
6. If you specifically want to call, scroll down that same page to Technical or Sales support phone numbers and choose your country/region.

Do not post your email address, password, subscription details, or telephone number here.

Shortest supported fix for the old account

Reinstalling Office does not necessarily remove its saved licensing information. Microsoft’s License Removal Tool clears all Office licenses stored on the Mac so that you can activate again with the correct account.^2^

Before proceeding: Have the email address and password for the account that owns the Office purchase or Microsoft 365 subscription. The tool removes local Office licenses, so you must sign in again afterward.

1. Quit Word, Excel, PowerPoint, Outlook, and other Office apps.
2. Sign in at Office.com/signin and verify that the intended account has the license you want to use.
3. Download Microsoft’s License Removal Tool.
4. Open the downloaded .pkg file from Finder → Downloads.
   • If macOS reports an unidentified developer, hold Control, click the file, and select Open.
5. Select Continue, follow the prompts, and then select Install. Enter the Mac administrator password if requested.
6. When the tool reports that the licenses were removed, select Close.
7. Open Word and sign in using the account associated with the valid Microsoft 365 or Office license.
   • If offered more than one license, Microsoft recommends selecting the Microsoft 365 license when available.
8. Restart the Mac after activation succeeds.
9. Delete the removal utility by moving Microsoft_Office_License_Removal from Finder → Downloads to Trash.

If this still fails, give Microsoft Support the exact message or error code displayed during sign-in or activation. For a work or school account, the organization’s administrator may also need to confirm that the account has a Microsoft 365 Apps license.^3^

References

1. Contact Microsoft customer support | Microsoft Support
2. How to remove Office license files on a Mac | Microsoft Support
3. [Activation](https://support.microsoft.com/microsoft-365-activation-licensing/what-to-try-if-you-can-t-install-or-activate-office-for-mac)