There are a few ways to unlock an Excel spreadsheet, but the easiest is to use a password. If you know the password, you can simply type it in and the spreadsheet will unlock. If you don't know the password, you can try to guess it. There are a few ways to do this. One way is to use a password cracker. This is a program that tries different combinations of passwords until it finds the right one. Another way is to use a brute force attack. This is a program that tries every possible password until it finds the right one.