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Apollo
06-11-2006, 04:47 PM
Wondering if I can make my password more dynamic and robust? Thus, making it more difficult for individuals to use a relatively simple software to crack the code.

I tried using this password [

amyjacksonBrianSmithjay
!!] and asked the IT department to crack the code. He uses a version for Office 97 and it cracked the code. Should I make it longer? Alternate upper and lower case letters?



Thanks,
Brian

Jacob Hilderbrand
06-11-2006, 07:27 PM
Unfortunately, making it longer or changing the case or introducing new characters will only make it harder for people trying to brute force (try all combinations) of the actual password.

What type of password are we talking about? Password to Open, Workbook, or Worksheet Protection, or VBE Protection.

Although we do not discuss how to crack protection here, I will say that the latter 3 types of passwords can be cracked in under a few minutes regardless of the lengths of the passwords.

The Open password is a bit tougher to get around but still doable if you use the standard 40-bit encription. If you use 128 bit or better, it would make it very difficult to be cracked.

File | SaveAs | Tools | General Options | Advanced |

Make the password at least 8 digits and include at least 1 lower case letter, 1 upper case letter, 1 number, and 1 symbol.

Also don't use real words, or reversed words, or dates.

Also note that Excel 97 is extreamly weak when it comes to passwords, and I believe you will not have the options for better encription levels until Office 2000 or 2002.

Apollo
06-17-2006, 09:38 AM
Protection for the workbook and worksheet (No password to open workbook, only insert sheets ect.). I realize that nothing is 100% secure. However, I use Excel for individuals to provide their quotes on. It makes it difficult for me when they change the format of the spreadsheet. I would just like to make the password as secure as possible.

johnske
06-17-2006, 01:31 PM
Don't confuse protection with security. Worksheet protection is not a security feature. Read http://j-walk.com/ss/excel/faqs/protectionFAQ.htm

Justinlabenne
06-17-2006, 11:33 PM
You can use a function like this to generate a harder to break password:

Option Explicit

Public Function GeneratePassword(Optional ByVal PasswordLen As Integer = 10) As String
Const sCharSet As String = "0123456789" & _
"ABCDEFGHIJKLMNOPQRSTUVWXYZ" & _
"abcdefghijklmnopqrstuvwxyz" & _
">/:-+="
Randomize
Do Until Len(GeneratePassword) >= PasswordLen
GeneratePassword = GeneratePassword & Mid$(sCharSet, _
CInt(Int((Len(sCharSet) * Rnd()) + 1)), 1)
Loop
End Function

'Test procedure
Public Sub GetNewPassword()
MsgBox GeneratePassword(30)
End Sub


A 30 character, impossible to remember password still will only last about 30 seconds max under good password cracking software, which your users can of course download for free all too easy.