[header] How to set, reset, remove and recover the password of excel files [title] Click on the office button, select prepare, and then choose encrypt document [title] Enter a password in the password box and then press ok. [title] Re-enter the previous password to confirm and then press ok. [title] Save the password and the ms excel 2007 document. 
[step] ( note: as microsoft advises, you must not forget the password or you will not be able to get into the document. If forget, you have to turn to third-party software like excel password rescuer for help.