Hacking Excel worksheet protection



Who hasn’t ever had the need to crack open a worksheet to see whats really going on?

Who hasn’t genuinely forgotten a password and needed to edit a sheet? or really taken over from someone who left after protecting loads of sheets with an unknown password?

All of those have happened to me, but the big one is I regularly get sent workbooks to review for some kind of repair/enhancement. Its impossible to follow the logical flow through protected worksheets, the auditing toolbar doesn’t work, select special doesn’t work, apparently blank cells may have hidden contents…

I guess a few of you know I’m not a fan of worksheet protection, so it will come as no surprise that I use the services of a password removal tool. There’s plenty of free VBA floating around t’interweb that will brute force a password. And some 2 line instant hacks for older versions. Some I tested do not remove all passwords – thats a PITA, after waiting 2 minutes.

VBA was too slow, so I went to a VB6 COM addin – for about a zero % speed up sadly. It still takes upto a couple of minutes on my laptop. Not good enough for a busy boy like me.

So I wrote an xll version which removes passwords in about 1 second on the same laptop. Its compatible with, and has been tested on, every (Windows) Excel from 97 to 2007.

Winter is coming

Winter is coming

As winter is coming (did it ever leave) and the smurflings need new shoes this is another commercial product. There is a free trial, and the full version only costs 20 quid (+HMRC cut of course) so its not like its going to bankrupt any other busy people who can’t wait 2 mins for a VBA version. Get in touch for details of multiple user discounts.

This only removes worksheet passwords and workbook structure ones, its doesn’t open or un-encrypt files saved with a password. If you can’t get into the workbook this tool won’t help.

All the details are here

The shop page is here

More on Excel security here

Its a proper commercial product so comes with full support, and you can buy in confidence knowing you are not funding drug cartels or people traffickers.

If anyone would like to incorporate a no user interface version into their products then give me a shout about possible licencing deals. I have already had some interest from some audit tool vendors, and you can be sure this will find its way into the next version of XLAnalyst (due out before Christmas (2008!))

Any feedback welcome, here or via email.



5 Responses to “Hacking Excel worksheet protection”

  1. Maarten van Stam Says:

    I guess you got your tax bills in the mail …. ? ;-)

    Another payware tool, I thought we agreed to drop the commercial deployments a couple of months ago (from the point of view that it is too much trouble to support customers, tool has to be bugfree, sets expectations for customers etc etc).

    Ow I forgot, you are in the UK where house prices are dropping! :-b


  2. Simon Says:

    Never mind the house prices, have you seen the stock market? Thats not great news for financial services opportunities is it?

    Good point on tax, I had forgotten about them.

  3. Stephane Rodriguez Says:

    “have you seen the stock market? Thats not great news for financial services opportunities is it?”

    Not sure what you mean. With options, you make money if you speculate in the same direction the market is moving, not if it falls.

  4. BAR Says:

    Are you saying there is now way to actually protect an opened Excel Workbook/Worksheet with passwords?

  5. Simon Says:

    Bar – not really, Excel is not meant to be a secure tool, its powerful and flexible, but not really secure.

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