since this morning I'm encountering wacky problems on my terminal server. I use user profile disks and they are getting slower and slower the longer the user session is. After 30 minutes it is so slow that apps like outlook, explorer and others starting to crash ending with a complet frozen session. After killing the user session and starting a new session everything works fine again. This is also independent from other user sessions. There can be 50% frozen and 50% fine working at the same moment. Apps and files on the local disk are just working fine (same disk where the profile disks are stored).
The event log shows up lots of cortana, searchui and ShellExperienceHost errors but nothing more.
I have no clue what could cause this.