Organizing and accessing contact information in Outlook on the web for business
The error message indicates a backend issue when adding a member, not a problem with the address itself. There is no specific fix for this error in the provided material, but the supported way to work around add-member issues is to invite the person via a share link instead of adding them directly.
To proceed, create and send a share link for the group so the user can join themselves:
- Open the group where the new member should be added.
- Create a share link for the group and send it to the intended member (for example, via email).
- Ask the user to open the link and join the group.
If errors persist even with a share link, contact support or post in the appropriate community forum for further investigation, as the issue is likely service-side.
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