The first things I would look at are to see if the file is shared or has grouped worksheets. To see this, while you have the file open, look at the title bar at the top. If you see [Shared] or [Group] it means one of those is turned on. My suspicion is grouped. To ungroup worksheets, simply right click on the current worksheet tab at the bottom and choose "Ungroup Sheets." I don't think a shared worksheet would cause this problem, but if that is it, let me know and I can tell you how to un-share a spreadsheet.