If you lost your group password from the Cisco IPSEC VPN but still have the PCF file, you can use this website to decrypt the encrypted password, located in the file. This is useful if you need to manually configure your VPN client (e.g. on a Mac, you cannot import a PCF file with the native VPN client).
To get the encrypted password, open the PCF file with a text editor (such as Notepad), then look for the line starting with enc_GroupPwd=. Copy everything after the = (if you have wordwrap on, make sure you got the entire line), and paste it in the text box on the website, then click the Decode button.