I am wondering if this my problem has something to do with Maverick update but my Mac Excel no longer works. I can save a file and it will open once but after that it will open but be completely blank. As for older files, ones that I desperately need, I keep getting this message: The file format or extension is invalid. Verify that the file has not been corrupted and that the file extension matches the format of the file"
I have spent hours on these forums and Mac forums reading about other peopel havign the issue and trying to troubleshoot it myself. I have already attempted opening the file by putting it in the shared folder and creating a new user. I have also cached the fonts, eliminated all fonts with warnings and duplicate fonts. I have gone into disk utility and repaired permissions. I have also tried software like Onyx to repair.I have also trashed Word font cache. Nothing has worked. Could someone please help me figure this out. I do have the files on an external hardrive and have tried uploading to a PC or Google Drive Spreadsheet and nothing has worked.
Does anyone have any suggestions or why this is happening. I no longer have the disk so I can't reload. I was wondering if my best bet now moving forward would be to revert back to an older operating system.
Any insight would be helpful.