We have observed that App volumes (UIA+Profile) disconnects randomly . Sometimes I can see the App volumes writable attached, when I log in to consequently I can't see the volume attached. Can you throw me a light where to start troubleshooting this issues???
Are you 100% sure it is indeed Appvolumes?
If so first thing to start looking at would be both Eventviewer and the svservice.log file. It could be that some info is stored there.
If you are using PCoIP as a protocol I would suggest looking into that logfile as well. It could be that the disconnect is triggered within the protocol.
Are you logged into other desktops at the same time? You can attach a writable ony one at a time. There is a setting that you can use to prevent a user from logging in to a seperate VM if they require that writeable.