I am using a DLL file as my license file for a VB.NET project and was wondering if there was a way to make it locked so notepad can't open it and edit the data stored in there. Thanks in advanced!

You can (and should) encrypt it. If you encrypt it as a file (versus just the contents) then users won't be able to copy/paste it to another computer (except when using Ghost or similar software).

Plus, when you say it will be unable to copy and paste from a computer to another computer, does this protect against them opening it and editing the data?

it will get corrupted when edited, and it they won't be able to read it.
Give me a few mins to google a tutorial or something for you.

I've found these:
http://support.microsoft.com/kb/301070
http://www.codeproject.com/KB/security/SimpleEncryption.aspx
http://www.codeproject.com/KB/security/EncryptFile.aspx

I can't find the "encrypt and prevent copy/paste" solution I promised, although I am aware of software that uses this.
I was just wondering if this was achieved by using the computername or something similar as part of the key, but that wouldn't work with Ghost (I used to prepare workstations a while back and was using Ghost to copy HDDs and then assign them computer names and this would work without a problem, but wouldn't if you copied it using windows copy/paste). In case anybody is wondering all copies were legal with full licenses.

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