•Take Full backup of the CRM databases
•Create a new Active Directory user “Test User”
•Map the effected user with this newly created users “Test User” in AD, save the changes once done, re-map the Test User account with Actual CRM user account(Domain\username) and then save and close the changes.
•Close all the IE windows , reopen IE and then test this behavior if the issue is resolve or not.
Thanks,
Mohammad