• I had a similar issue, a user changed their AD Login details and for some reason the old username was still being passed to SQL Server. The user had access to the Database via a security group so no changes there were required.

    We confirmed the change had replicated to the DC, the issue was happening on multiple different machines ie it wasn't cached on a specific workstation.

    When profiling the old username was appearing but they were able to connect, I'm assuming via the Security Group.

    When running xp_logininfo 'DOMAIN\oldname' & xp_logininfo 'DOMAIN\tnewname' both commands would return details of the user as if they both existed on the DC. Running the same command would fail for the 'DOMAIN\oldname' from any other server.

    So by this point the issue was narrowed down to the SQL Server itself, something was caching the user details. I tried clearing the TokenAndPermUserStore hoping that would solve the problem but no luck.

    Due to time constraints I ended up dumping the cache (DBCC FREEPROCCACHE & DBCC DROPCLEANBUFFERS) and it solved the problem.

    So now I'm trying to work out where exactly it was cached so if it happens again I can fix it in a nicer cleaner way.

    Any ideas?

    Cheers