This problem is only appearing under the following circumstances:
- a LDAP server (OpenLDAP, Active Directory, ...) is used
- the server uses referrals
- "Follow Referrals" in the Advanced User Settings (JIRA Administation > User Directories) is checked
Unfortunately, User Profiles for JIRA does not currently support ADs with referrals yet. The issue is tracked in UPJ-52.