So in the ongoing quest to get a XenDesktop 7 environment going. I was having a problem where, when logging in as a non-admin user, the desktop would appear for a split-second -- you could just make out the windows login screen -- before kicking the user back to the XenDesktop login (Wyse Xenith 2 login, in this case).
The only Error in the event log, the one that makes this posts title, was as follows
- Error | ICA Service | EventID: 34 | ICA Connection Request denied because AutoLogon was not possible and EnforceAutoLogon is active.
Googleing this error code returned nothing, 0 results. Googleing the symptoms returns some things, but nothing that solved my problem.
In my case it was simple and stupid. I had put these new machines in an old OU in AD. This OU had, unbeknownst to me, a GPO which denied local login to non-admins (OU was for remote-desktop machines in the past). Removing the GPO fixed everything, go figure.
If this isn't the case in your situation, the error so far as I can tell, is caused when the pass-through authentication fails. This can be caused by any number of things (like bad GPOs), and there's a lot of good support forum posts about the non-stupid causes of this problem, so I won't go into much detail here. But here's some things I researched that might get you pointed in the right direction.
XenDesktop Passthrough Authentication failure:
Exact symptoms I described, but with a different cause:
