How can I decrypt a VPN pre-shared key?

I have a windows 7 *.cmp file which contains an encrypted pre-shred key in it and I also know the pin-code for it.

[Profile Format] Version=5 [Connection Manager] CMSFile=xxx\yyy.cms PresharedKey=*************== PresharedKeyIsEncrypted=1 

The question is what do I do to decrypt the key and view it in plaintext?

1 Answer

If your up for a little programming, it looks like it has been answered on SO

and that contains a link to some sample code

otherwise there are probably a few programs that can do it, but that might be more of a question for software recs than here