Microsoft is restricting older Office licences: certificate expiry affects Office for Mac 2019 and 2021

Users of Microsoft Office for Mac 2019 and Office for Mac 2021 should take note in the coming weeks. Microsoft has announced that an important digital certificate used for licence validation is due to expire. If this is not updated in good time, Office applications may no longer activate correctly or may only be usable to a limited extent.

Users of traditional perpetual licences who do not have a Microsoft 365 subscription are particularly affected.

What happened?

Microsoft uses digital certificates to verify the authenticity of software components and the validity of licences. If such a certificate expires, Office can no longer reliably determine whether a licence is valid.

The following are particularly affected:

• Microsoft Office for Mac 2019
• Microsoft Office for Mac 2021

Whilst Microsoft 365 is updated regularly and automatically receives new certificates, users of older purchased versions must ensure themselves that the latest updates are installed.

Cut-off date: 13 July 2026

Of particular importance is the 13 July 2026. On this date, the certificate previously used for licence validation will expire.

For users of Office 2019 for Mac This could have serious consequences. As support for this version has already ended, Microsoft no longer provides updates with a new certificate. After the deadline, the applications will switch to a restricted mode. Documents can still be opened and printed, but it will no longer be possible to edit, save or create new files.

Users of Office 2021 for Mac can, however, avoid the problem provided they install the latest updates. These already contain the necessary adjustments for the new certificate.

What are the potential consequences?

Depending on the version of Office you are using and your update status, the following issues may occur:

• Activation error when launching Office applications
• Error messages during licence verification
• Problems with new installations
• Restrictions on the use of certain functions
• Switch to restricted read-only mode

This is particularly critical for companies that still use older versions of Office in a production environment or keep spare devices running older versions of the software.

What does Microsoft recommend?

Microsoft recommends installing all available updates for Office for Mac as soon as possible.

The following steps are recommended:

1. Update Office to the latest available version.
2. Use the current installation files before performing a new installation.
3. Document licence information and login details.
4. Check whether the version of macOS you are using supports the latest Office updates.
5. If necessary, plan to switch to Microsoft 365 or a newer version of Office.

Why does this mainly affect permanent licences?

Perpetual licences are often used for many years and frequently no longer receive any major technical updates. Once support ends, even key components such as certificates are no longer updated.

For years, Microsoft has been pursuing a strategy that focuses on Microsoft 365. Security updates, certificates and feature enhancements are provided on an ongoing basis through this platform. Users of older, purchased versions, on the other hand, must expect to face technical limitations once support expires.

What should companies be doing now?

IT managers should check as soon as possible which versions of Office are installed on their Mac systems.

In particular, the following questions should be answered:

• Is Office 2019 for Mac still in use?
• Are all Office 2021 installations up to date?
• Are there any spare or replacement units with older installation versions?
• Is the version of macOS I'm using still compatible with the latest Office updates?

By checking these points at an early stage, you can avoid downtime and reduce the need for support.

The expiry of the Microsoft certificate on 13 July 2026 marks an important deadline for users of Office for Mac. Whilst Office 2021 for Mac can continue to be used without any problems thanks to the latest updates, users of Office 2019 for Mac significant limitations, as this version no longer receives certificate updates.

Businesses and home users should therefore check their installations in good time and, if necessary, plan to migrate to a supported version of Office or Microsoft 365. Taking action now will help avoid any unpleasant surprises after the deadline.