I have a file that was created with excel 2007. We have move on now to excel 2013 (office365). This file track our utilization and contains a lot of data that I cant afford to lose. The problem is I can open it in excel 2013. I can make changes and do what I need to do but when I try to close and or save the file i get a error stating that Microsoft excel has stopped working. I really need to figure this out. Thanks in advance on any help you might be able to give me.