I am using Info.display("", "My message");to display GXT Info box on screen but it is observed that the info box is not rendered properly (with a transparent background not readable properly) in some of user system.
This issue is solved when user clear browser cache and delete temp folder files and start a new session, but the problem is replicated again after some time interval.What could be the reason? I am not able to debug because Message div is deleted in a fraction of 3-4 seconds.I am using sencha 3.0 version.
Your problem sounds similar to the one described in this Sencha GTX 3.x bug report:
http://www.sencha.com/forum/showthread.php?282275-Info-popup-is-transparent-in-IE
You may wish to follow its progress if this issue is still important to you.