File and VBA Project passwords

On another page, I detail how XL's internal password protection works, and how it can be removed. These Worksheet and Workbook passwords are very different from File and VBA Project passwords.

File Protection

File protection (applied when the file is originally saved using SaveAs and clicking on the Options button) is quite a bit more robust than XL's internal protection. However, relatively inexpensive commercial password crackers are available, either as stand-alone applications (all for Windows, currently) or as a service that you send the workbook to. Dictionary attacks can be very quick (seconds to hours). Brute force attacks can take much longer - and probably aren't worth it if the password is likely to be over 8 characters. Do a Google search or check the newsgroup archives to find a recent list of providers. XL MVP Chip Pearson also has a list of providers (though, like me, he's never used them).

Decryptum.com guarantees free on-line removal of most file passwords, usually within 3 minutes. You can then pay to download the unprotected file. (Disclaimer:while I've never paid for a download myself, if you follow this link and end up paying to get the download, I may receive a commission.)

Note that file protection is not encryption - you can use a hex editor to examine files and, while the result isn't entirely human-readable, one can often view the general layout, as well as any text.

VBA Project Protection

In principle, VBA Project protection (applied by choosing Tools/Project Properties in the VBE, checking the Lock Project for Viewing checkbox and entering a password) is also more robust than worksheet/workbook protection. Unfortunately, while the technique is not well known, VBA Project protection can be bypassed easily with a hex editor. Commercial services also are able to remove such protection in a heartbeat.

As with file protection, a hex editor can also lay bare your VBA macros. Macro keywords are tokenized, so it's not directly human-readable, but it's often easy to figure out program flow, look at constants, etc.

This page last updated Thursday, 23 December 2004