liggyman's blog

I converted my main workstation at home to a virtual machine, and started connecting to it via RDP from a thin client machine. I found that images didn’t look quite right, and had banding instead of proper gradients. The color depth was set to 16-bit and couldn’t be raised, even when setting the depth higher using the RDP client.

Remote Desktop server on Windows XP, by default runs at a maximum 16-bit color depth. However up to 24-bit color is supported.

This can be enabled by modifying a Group Policy setting:

The Group Policy setting which controls this is located at:
Computer Configuration\Administrative Templates\Windows Components\Terminal Services\

And is called:
‘Limit maximum Color Depth’

Enable this setting, and set it to ‘Client Compatible‘ or ‘24-bit’.

To change this setting on the local machine you can follow these steps:

1. Open up the Group Policy editor, by going Start -> Run… and type in MMC.
2. Add the Group Policy snap-in by going to File -> Add/Remove Snap-in -> Add -> Group Policy Object Editor -> Add -> Finish (Local Machine) -> Close -> Ok.
3. Now navigate in the Group Policy Object Editor to Local Computer Policy\Computer Configuration\Administrative Templates\Windows Components\Terminal Services and double-click on the ‘Limit maximum Color Depth’ object.
4. Click on ‘Enable’ and choose either ‘Client Compatible’ or 24-bit

Now you should be able to run in up to 24-bit on Windows XP via your Remote Desktop connection.

Additional:

Options include 8-bit, 15-bit, 16-bit, and 24-bit allowing you to force lower bit depths.

This entry was posted on Wednesday, March 11th, 2009 at 8:58 pm and is filed under IT issues, Knowledge Base, Tips. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.