Is there any way to restore back an excel file to a previous version?

Question

Roll back changes made by mistake in Excel 2007. The windows 7 system protection option was disable.

Answer 1

1. If you have backups, then there you go.
2. If you used "Save version" functionality, you can open previous version.

Otherwise you are out of luck, unless you didn't close Excel (and that file). In that case, you can just undo your changes (Edit->Undo, or ctrlz).