Saturday, April 18, 2009

24 bit RDP under Windows XP

Just recently during (probably my last) Sunray/VDI demo installation I ran into the problem that we could not get 24bit color depth on the virtualized Windows XPs.

The SunRay part of the installation (i.e. the Desktop Unit (DTU, aka. ThinClient) itself could not be the problem, because they always are 24bit (incl their respective X session on the SunRay Server),
we also ran the RDP client (uttsc) with the -A 24 option to force it to 24bit (which it would default to anyway) ... but to no avail.

Of course as always google is your friend; several people have posted and blogged this already: under Windows XP you have to explicitely enable 24bit for RDP. So in the Windows XP image (or template) open the registry and change

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Terminal Server\WinStations\RDP-Tcp\ColorDepth

to the value 4.
Not sure if you have to reboot the virtual machine (VM) then, but since rebooting a virtualized XP is quite fast anyway, just reboot it...


parlevjo said...
This comment has been removed by the author.
parlevjo said...

"to the value 4"

Must be

"Change colordepth to 4."

Roman said...

@parlevjo: yes, of course. fixed this, thanks