Creating a custom encrypted file to use it as product key

[Victor Torres]

Hi to all, I'm looking for a way of creating an encrypted file that my
front-end ms access database will look and if the file exist and the data is
correct then will run. I know how to do the trial and I know that using the
custom properties is a way of doing it but I want to see if this is posible
and how can it be done. Here is an example of what I want. I want that if
the file xxxxx.key is in the same folder as the database and for example the
data read like this:

iutIU1YIfiFYIfiFyiFuoiulgIYf2uFlifvLYIfyif
jfiy3Tifli.gfLIfiyR&4IFVE5e86rF795fyi9f
(7t79R6e%iyfUIuR67343wyifIYf90tgu67
*&587r86ydUyr67RE86R9tlg80Y90645

the system can identify the code that is inside

iutIU*1*YIfiFYIfiFyiFuoiulgIYf*2*uFlifvLYIfyif
jfiy*3*Tifli.gfLIfiyR&*4*IFVE5e86rF79*5*fyi9f
(7t79R*6*e%iyfUIuR6*7*343wyifIYf90tgu67
*&587r*8*6ydUyr67RE86R*9*tlg80Y90645

123456789

Can access do this?

 

[Victor Torres]

Hi, I was looking in the net for this problem and found out almost the same
that I want but without any explenation of how it is done. The site is
http://www.granite.ab.ca/access/demo.htm
Can anyone let me know how to do this? Thanks...

 

[Tony Toews [MVP]]

Hi, I was looking in the net for this problem and found out almost the same
that I want but without any explenation of how it is done. The site is
http://www.granite.ab.ca/access/demo.htm
Can anyone let me know how to do this? Thanks...

Yes, that's my page. And no I didn't post any code as I do *not* want
to be liable for someone else's mistake.

The first line in my key file is a line that states in clear text
"Granite Consulting License Key File" so that someone looking at this
will have an idea of what the file is all about.

I would strongly urge using the CryptoAPI as specified by Microsoft.
Read the documentation thoroughly.

See Security Alert: Debian & Ubuntu Linux Weak Encryption Keys
http://www.cmu.edu/computing/news/security/2008/may/051608-1.html
DSA-1571-1 openssl -- predictable random number generator
http://www.debian.org/security/2008/dsa-1571

My point is that rolling your own solution can cause problems.

How to encrypt a string in Visual Basic 6.0 and how to decrypt the
string in Visual Basic .NET or in Visual Basic 2005
http://support.microsoft.com/kb/821762 will give you enough keywords
to continue searching.

Tony
--
Tony Toews, Microsoft Access MVP
Please respond only in the newsgroups so that others can
read the entire thread of messages.
Microsoft Access Links, Hints, Tips & Accounting Systems at
http://www.granite.ab.ca/accsmstr.htm
Tony's Microsoft Access Blog - http://msmvps.com/blogs/access/

 

[Victor Torres]

Thanks Tony... You're one of the best! I'm just looking for a simple but
jet, powerful security system. Like in your example I know that limiting the
number of users or records has to be one of the best methods out there but
I'm trying to go beyond that. I already found out how to retrieve the
Microsoft Windows Product Key (Not the ProductID) and combine it with a date
creating a unique code. My apps will look for the day plus or a qty of
opens. So if they manage to trick the date they will have from 100 to 200
opens until the program stop. What I'm looking right now is creating a
xxxx.key file that will have the code inside it but when someone open it will
only see garbage. Anyway thanks for your help. I will look at those pages to
see if I can find out how to accomplish this.

By the way, can you or someone else tell me how to do a random with letter
and number? I try to look for this in the web with no luck. I think this is
by using array but I'm not an expert in vb. Thanks for any help that you can
give me.