Symptoms

We have several users that cannot work in ANY app that uses K2 - they suddenly lost all their group memberships
 

Diagnoses

When a user loses its AD group memberships what could be the cause here.

When K2 tries to retrieve user info from AD it logs:

IdentityServiceError","IdentityService.ProviderCacheIdentity:RoleProvider.GetUser","64007 Provider did not return a result for user.

What could be the cause of this error ?
 

Resolution

Please check to see if the group being used in question has any symbols within it. Best place to check this is from AD itself.