At work, I recently needed to edit a database connection string in an Excel spreadsheet. Unfortunately the macros were password protected, the person who wrote the spreadsheet left the company some years ago, and we had no record of the password.
Luckily, thanks to a post on David Bugden’s blog, I discovered that it’s simple to circumvent VBA macro password protection without having to purchase a commercial utility such as Passware’s VBA Key.
The hex editor method worked for me in Excel 2003, although I’m not sure whether Microsoft have beefed up the security in 2007 and later versions.
If you want to remove the password used to protect/unprotect worksheets and workbooks, there is some information available here.