My sister has a Dell Inspiron 15.6" laptop, and I custom-installed Windows 7 Professional on there for her (it came with Home Premium).
I got all her programs transferred from our family computer and it worked perfectly until I upgraded it to IE9. What ends up happening is that there's a weird black bar on the far right side of the screen - even if you have it in window mode and try adjusting the window, that bar is always there. It shifts the entire screen over a few pixels but the mouse is set to its "normal" position - as in, you have to click and drag in that black box to use the scroll bar, and for clicking links you have to move the mouse off to the right by that amount. Needless to say it's very frustrating.
For the time being I rolled-back to IE8, and will keep my sister on that until I figure out how to fix 9. (She doesn't know much about computers, she tends to just use them the way I set them up for her)
Here's a screenshot showing what I mean:
As you can see that's the initial setup. I tried going into Internet Options and doing a complete factory reset of IE, I even disabled it in the control panel and re-enabled it. None of that worked.
Anyone else had this problem? I can't seem to figure out what the heck is going on. That bar is there for any website you go to - and as you might notice, the "compatibility view" button is completely gone, and compatibility view itself does not work.