Yes you can but sometimes it depends on whether or not there is wire in the glass, if it is double paned which can affect the angle of the dish among other things. It has been a little while since this has been discussed but it has and can be done.
It can be done and Ive done it but the glass and frame plays a roll as well as placement of the dish. I did one in a third floor loft / storage area in one of them old small town main street style buildings. The windows were about 100 years old if a day and with them closed it killed the signal down to %60, with them open it was at %95 so the glass and its frame played a role in the signal degridation.