Blog Post

Microsoft Mission Critical Blog
7 MIN READ

SharePoint and OneDrive Site User ID Mismatch Explored

Tania Menice's avatar
Tania Menice
Icon for Microsoft rankMicrosoft
Mar 03, 2026

A user leaves your organization. Months later, a new hire is assigned the same email address. When inspecting the users’ permissions everything looks correct, but SharePoint continues to return Access denied for certain sites, generates an unexpected OneDrive URL suffix, or behaves inconsistently when trying to access content. In many cases, the root cause isn’t permissions at all, it’s an identity mismatch that SharePoint is designed to catch.

    In this post, we walk through why users who look ‘healthy’ on the surface can still experience issues, and we cover practical ways to prevent and fix them across identity lifecycle manag...
Updated Feb 23, 2026
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mw365
wroot's avatar
wroot
Silver Contributor
Apr 30, 2026

Real world scenario is people returning after long maternity leave when they accounts are being deleted on departure and created fresh with the same email/UPN (obviously) when they are back. Usually we get tickets from customers when user is already back and they already have some new files shared with them and then they try to access and older file and get the error. I know that doing cleanup during offboarding would be ideal, but we do not always control how our customers do things. So, currently we are running ID mismatch fix on a case by case scenario (one site of a file at a time/ticket), which is of course frustrating both for us and the users. MS can come up with a mechanism to enumerate all current user's access and cleanup all older UILs in one action instead of hunting them one by one.