I have a new HP lap top running windows 7 and excel 2007. When trying to switch from one sheet to another in a workbook sometimes it goes and sometimes it doesn't. If the sheet doesn't change the highlight on the current cell will disappear but the cell identification in the name box doesn't change. I can usually jump to a different sheet by clicking twice on it and then maybe click back to the sheet I really want. I have run excel diagnostics and uninstalled then re installed office. This happens with all workbooks that I have run on the new lap top but all of the workbooks run fine on any of several XP machines that I have access to. Anybody have an idea?