This drove me nuts for ages, especially with predominantly black walls......boss gave me this code.....
If you change line 14 in the uifile from this:
background: rcbmp(100,6,0,sysmetric(0),sysmetric(1),0,0);
to this:
background: rcbmp(100,6,#FF00FF,sysmetric(0),sysmetric(1),0,0);
will fix the problem...
"If you are creating the logon with Logon Studio, you need to change that line as the VERY LAST thing you do, because once you open it with the LS editor again, LS will change it back".
hope this helps....
(copy/pasting the code is safer that retyping.....from experience...

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