Remote Desktop PassView is a small utility that reveals the password stored by Microsoft Remote Desktop Connection utility inside the .rdp files
Using Remote Desktop PassView
Remote Desktop PassView doesn't require any installation process or additional DLL files. Just copy the executable (rdpv.exe) to any folder you like, and run it. After you run rdpv.exe, the main window display the passwords of .rdp located under your "My Documents" folder. The default .rdp file (Default.rdp) is usually stored in this location
If you want to recover that password of another .rdp file, just drag the file from Explorer into the window of Remote Desktop PassView utility or use the "Open .rdp File" option from the File menu.
Be aware that Remote Desktop PassView can only recover the passwords created by your current logged on user. It cannot recover the passwords of .rdp files created by other users.