This is a very Weird behavior that I came across...

When loading an <ext:Window with Data from .ashx file, it works on IE7, IE8, FireFox. But in some cases a few users complains that when they click on the link that Pops up the <ext:Window , the Progress Bar on the IE browser NEVER completes and just some Data displays on the Window.

The other strange behavior is when the Users Tab over to a next tab, then Tab back to the current Page, the Progress Bar Completes loading in the Browser...

I have confirm that the IE Browser versions are identical, but in some cases the situation above happens...

Any idea why this occurs???