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Re: Question

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> Hey I would like to know how this works, How Excel file can be open  
> with these generated usable password, what is the logic behinds this 
> scenario.
>
> AABBAABBBAAW  equals to 12345 in what sense ?
>
> Cracked password                     Lock password
> One usable password is AABBAABBBAAW	12345
> One usable password is AAAABAABAAAx	allthebest
>
> Regards,
> Mandeep baluja 

How passwords work is by comparing a hash of the stored password 
against a hash of the entered password. This means several different 
strings *could* (in theory) generate the same hash.

If you want to lock unauthorized users out of your file you'll need to 
implement encryption methodology that is managed via VBA, so only 
certain sheets are viewable or editable by certain users.

This allows anyone to open your file, but all that displays is a login 
sheet, and all other sheets are 'very hidden'. The login data is stored 
on a 'very hidden' sheet in encrypted format.

The encryption methodology you use could use a simple Xor function, or 
one of the CryptoAPI algorithms that require an encryption key/seed. I 
use the latter because I already have licensing/activation methodology 
in place for my apps where each has their own unique 40-character 
encryption key so the key for App1.xla won't work with App2.xla, for 
example.

None of this matters unless you can lock your VBA project *securely* 
with a 3rd party utility like Unviewable+ or similar!

-- 
Garry

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Question Mandeep Baluja <rockernayal@gmail.com> - 2016-01-06 03:57 -0800
  Re: Question GS <gs@v.invalid> - 2016-01-06 09:16 -0500

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