I suspect a CMP file is a compressed files. Assuming you are talking about Remote Access Server CMP files, they can contain user account information, so I suspect it is locked down from 'soft' inspection.
I couldn't find any reference to opening them via VB.
But it might just be worth changing the file extension to .zip to see if it is a standard compressed file. If it is, there are many vb .net methods available.
If not and you can find out what type of compression or encryption is used, you may be able to find specific libraries for them.
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