Hi,
I have tested this issue with v.4.1.0.50 in Windows XP SP2 and Windows 2000. For some reason, I am unable to reproduce the problem. The TabBackColor correctly gets displayed in the tabs in XP and Win 2000. Please refer to the screenshots attached below
Please let us know the version of Essential Studio you are using. Also, could you please provide the sample that shows this issue?
Regards,
Mano
Snaps_TabBackcolor.zip