Password protection query (I don't need to break one myself)

[AndrewRossington]

I have an excel document that has password protection.

Tools > Protection > Protect Sheet.

This goes out to over 300 people soon, and I just wondered how secure it is right now. I've done a quick search on the internet and found software available for purchase that can remove passwords.

My question: Does anyone know of software that is free for download, how easy it is to find, and if it's good enough for me to worry that my spreadsheet security could be compromised by a relatively inexperienced computer user. (I don't need to know what it is)

Does anyone have any suggestions of how I can add additional security to block editing?

Thanks

 

[DominicB]

Good morning AndrewRossington

Software to remove this type of protection is certainly available free of charge and very easy to find (there are even macros available to do it!) Perhaps that should tell you just how flimsy it is. Excel is not secure, and any type of protection offered can be bypassed.

That said, there is a third party app available (that has been advertised on the MrExcel pages recently) that claims to make excel more secure, but I can't say how secure this is. I just can't remember the name right now...

HTH

DominicB

 

[AndrewRossington]

Thanks pal, this helps.

 

[SydneyGeek]

I have been working for a few years with workbooks that I distribute to numerous users. All worksheets are password-protected.

I do occasionally let users know the password if they *really* get stuck -- happened earlier on, very infrequently now. If that's the case, next reporting cycle there is a new password on it. Over 7 reporting cycles and a fair bit of hammering, I haven't seen any compromised (ie stuffed) workbooks.

Yes, there is password-cracking software out there. Yes, someone may download it. But if you have thoroughly tested the workbook and caught all the possible glitches, they won't have a reason to.

Denis

 

[AndrewRossington]

Thank you, sir.

It also depends on much you trust the people you're sending it to. I guess I'm trying to be overly cautious just in case someone tries to screw us.

 

[SydneyGeek]

Just a question:

Will the users be doing any data entry, or will they just be viewing the files?

If they are just viewing the data, why not send out PDFs? Even if they do convert the PDFs to spreadsheets they will only get the data, not the formulas.

Denis

 

[AndrewRossington]

Just a question:

Will the users be doing any data entry, or will they just be viewing the files?

If they are just viewing the data, why not send out PDFs? Even if they do convert the PDFs to spreadsheets they will only get the data, not the formulas.

Denis

They'll be entering data. This spreadsheet calculates payments due, and as such I don't want them to be able to change the formulas in their favour.

 

[Doug.T]

Is this an internal company spreadsheet? I don't worry too much about employees breaking sheet protection. Such hacking behaviour should be covered by their employment contract or their employer's Code of Conduct.... with resulting CLM consequences. If someone hacks a spreadsheet in thier favour (I've had this happen on IRR & Budget submissions) take it up the ladder.

 

[SydneyGeek]

One thing I have done for peace of mind, is record a macro that harvests all the formulas. With a bit of editing you can create a routine that
(a) unprotects the sheet
(b) resets all the formulas
(c) protects the sheet

If you reckon something's been tampered with, reset it. Works fine it you have a set structure, and it sounds like you may well do.

Denis

 

[DominicB]

Hi AndrewRossington

Just found the link for the software I mentioned in my post above :

http://www.excelshield.com/

...but like I said, never used it so can't comment on how good it is. Purely for your information.

HTH

DominicB