I have a 2004 Chevy Express van and the window stops open at an inch or two and wont go any further. They are manual windows that had an aftermarket power kit added. I have removed the kit and even with the handle the window stops at the top.

The gear crank inside the window has skipped some teeth - pull the crank out and start over - that is all it can be from the way they are made - pull the gear out and just shove the window to the top - if it goes all the way to the top then you know the crank skipped like a chain on a bike - reset it and you should be good to go.