I've put it up on double pane windows without any problems. The manufacturer I used recommends leaving 1/16" around the edges to allow for expansion and contraction. It is possible that your window manufacturer may void the warranty if you still have one. I guess it depends on if the windows are made to proper specifications. ... View related article.
I've heard that cayenne pepper works. I think it has to be re applied periodically, especially after it rains. It is not as expensive if you buy it in the bulk section. Rocks can help too, since it isn't 'dig friendly' for cats. The catnip mentioned below is a good idea. My neighbor cats go straight for that! ... View related article.
