I have a user that the tool palettes keep going transparent even though they aren't set to go transparent. The most common one to go this way is the Layer Manager Palette. The only way to get them to come back is to exit ACA and restart it.
I updated the video driver and that didn't help.
ACA 2011 with update 1 and Windows XP
Thanks for the help
Does your user have an add-on in ACA?
Is there another ACA user with the problem?
Does the issue go away if another ACA/AutoCAD profile is used at that one PC?