I tried preloginloader 3.4-31 - which doesn't work at all on Vista, as far as I can tell. I get errors in my clientconnect log when using it:
[3] [Oct 15 06:32:26] [opsiclientd] Refusing to set empty value for config value 'block_notifier_command' of section 'opsiclientd_notifier' (opsiclientd.pyo|2294)
[0] [Oct 15 06:32:26] [opsiclientd] Opsiclientd version: 0.5.9 (opsiclientd.pyo|2700)
[0] [Oct 15 06:32:26] [opsiclientd] Commandline: C:\Program Files\opsi.org\preloginloader\opsiclientd.exe (opsiclientd.pyo|2701)
[0] [Oct 15 06:32:26] [opsiclientd] Working directory: C:\Windows\system32 (opsiclientd.pyo|2702)
[2] [Oct 15 06:32:37] [event gui_startup] Ignoring wql param because event type is 'gui startup' (opsiclientd.pyo|214)
[2] [Oct 15 06:32:37] [event wait_for_gui] Ignoring wql param because event type is 'gui startup' (opsiclientd.pyo|214)
[2] [Oct 15 06:33:03] [action_processor_starter.exe] Cannot mount: (1312, 'WNetAddConnection2', 'A specified logon session does not exist. It may already have been terminated.') (Windows.pyo|258)
[1] [Oct 15 06:33:03] [action_processor_starter.exe] Traceback: (Logger.pyo|646)
[1] [Oct 15 06:33:03] [action_processor_starter.exe] line 86 in '<module>' in file 'action_processor_starter.py' (Logger.pyo|646)
[1] [Oct 15 06:33:03] [action_processor_starter.exe] line 259 in 'mount' in file 'OPSI\System\Windows.pyo' (Logger.pyo|646)
[1] [Oct 15 06:33:03] [action_processor_starter.exe] ==>>> Cannot mount: (1312, 'WNetAddConnection2', 'A specified logon session does not exist. It may already have been terminated.') (action_processor_starter.py|99)
[3] [Oct 15 06:33:03] [action_processor_starter.exe] Request to '
https://localhost:4441/opsiclientd' failed: (10053, 'Software caused connection abort'), trying to reconnect (JSONRPC.pyo|319)
[2] [Oct 15 06:33:04] [action_processor_starter.exe] Failed to process action requests: Cannot mount: (1312, 'WNetAddConnection2', 'A specified logon session does not exist. It may already have been terminated.') (action_processor_starter.py|103)
preloginloader 3.4-30 seems to work OK. I'll roll it out and see if that fixes the issue we're hitting.