Departments Menu Glitch - NAV 2009 / R2

Departments Menu Glitch - Assign Users 

In Navision 2009 / R2 (Classic) you are able to hide departments from your users, however somtimes this can glitch. I've witnessed this issue a few times whereby the you disable / enable a department for a user but nothing happens.

The quick fix is to delete the user completely from NAV.

Tools >> Security >> Windows/Database Logins >> Copy all the permissions >> Delete the User >> Synchronize >> Re-Add the user >> Paste the logins back in >> Synchronize.

As to why this happens, I have no idea. I think the 'User Menu Level' gets corrupted.