When connecting to a Windows Server 2003 computer using the Windows Server 2003 Remote Desktop Connection client, the default color resolution is 256 colors.
You can use Group Policy on the Windows Server 2003 computer to set the maximum color resolution an RDP client can use, a value that should NOT exceed the capability of your video adapter:
1. Open the appropriate policy, domain or local.
2. Navigate through Computer Configuration / Administrative Templates / Windows Components / Terminal Services.
3. Double-click Limit Maximum Color Depth, enable the policy, and set the maximum color depth.
4. Press Apply and OK.
When a client wants to connect:
1. Start / Programs / Accessories / Communications / Remote Desktop Connection.
2. Type the name of your computer.
3. Press the the Options button.
4. Select the Display tab.
5. Select the color resolution they desire.
6. Press Connect.