I'm running Office 365 on Windows 8.1. Excel was working fine until today. When I went to open any spreadsheet that is on our network drive and created by other users, the spreadsheet almost looks like a screen shot as if someone inserted a picture. The tabs (Sheet 1, Sheet 2, Sheet 3) are not at the bottom and are embedded into the document itself. I can only see columns A - G and cannot see anything further than that. However, when I go to create a new spreadsheet, everything is fine. It's only when I open other spreadsheets that this anomaly occurs. 
Can someone help to figure out what could be causing this problem? As I said, everything was fine until today. The only thing I did differently was enable PowerPivot.
Can someone help to figure out what could be causing this problem? As I said, everything was fine until today. The only thing I did differently was enable PowerPivot.
