"An update is required for this add-in" where Update Now button does nothing

The message indicates that Word believes the add-in’s manifest has changed in a way that requires re-consent or reinstallation, but the update flow for this specific user is stuck.

From the provided information, the key points are:

1. Any change to the XML manifest requires the version to be incremented.
   • The <Version> element must be incremented whenever the manifest changes so that the new manifest overwrites the existing one and users receive the updated functionality.
   • If the add-in is store-distributed, the new manifest must be re-submitted and approved before users receive it.
2. Certain manifest changes force an admin/user re-consent and block usage until consent is granted.
   • If requested permissions change, users are prompted to upgrade and re-consent. If the add-in was installed by an admin for the organization, the admin must re-consent first; users cannot use the add-in until that consent is granted.
   • For centrally deployed add-ins, changes to requested permissions, scopes, or events in the manifest require admin consent again. Users remain on the existing version until consent is granted.
3. There is a known class of issues where Office add-ins fail to update correctly for some customers.
   • Some customers experience add-in update failures through the Store, leading to activation issues and the add-in becoming unavailable.
   • The recommended actions are:
     1. Restart the Office application.
     2. Wait and retry the update after some time.
     3. Ensure the Office application is on a supported and up-to-date version.
     4. If the issue persists, collect and share diagnostic information (session logs, network traces) with support.
4. If the add-in package or manifest is not correctly updated or is invalid for that user’s environment, Word can block the add-in.
   • When installing or updating, if the manifest validation fails or the package was tampered with, Word shows errors and the add-in cannot load until a valid package is installed.

Putting this together for the scenario:

• Most users updated successfully from 2.6 to 2.8, so the deployment and manifest versioning are generally correct.
• For the single affected user, Word has detected that an update is required (likely due to the new manifest version) but is failing to complete the update or re-consent flow. This aligns with the known issue where add-in updates can fail for some customers, leaving the add-in unavailable.
• The “Update now” button doing nothing suggests that Word cannot retrieve or apply the updated add-in package for that user (for example, due to a transient store/update issue, cached content, or an incomplete update state on that client).

Practical steps based on the documented guidance:

1. Confirm the manifest versioning and any permission/scope/event changes
   • Ensure the <Version> element was incremented when going from 2.6 to 2.8.
   • Confirm whether any requested permissions, scopes, or events were changed. If so, verify that the admin has granted consent for the updated manifest, because users are blocked until consent is granted.
2. On the affected client, try to clear the update/activation issue
   • Close Word completely and restart it, then try the add-in again.
   • Ensure the user’s Office build is supported and up to date.
   • If the add-in is store-based, allow some time and retry, as propagation and retries can resolve partial update states.
   • If the issue persists only for that user, consider removing and re-adding the add-in for that user so that Word downloads a fresh copy of the manifest and package.
3. If the problem continues only for that user
   • Collect diagnostic information (session logs, network traces) from that client and provide them to Microsoft support, as recommended for add-in update failures.

The reason this appears only for one user is most likely a client-side update failure or partial state on that specific Word installation, combined with the requirement to apply the new manifest version (and any associated consent) before the add-in can be used.

References:

• Troubleshoot user errors with Office Add-ins
• Update and maintain your Office Add-in
• Office Add-ins known issues
• Office Add-ins with the add-in only manifest