1. Obtain a copy of DebugView from this location: http://technet.microsoft.com/en-us/sysinternals/bb896647.aspx
2. Run DbgView.exe on the Popup Client machine. Check the Capture menu, and be sure that "Capture Win32" and "Capture Events" are both enabled.
3. Select "Log to File" from the File menu and provide a suitable filename.
The various Popup Client components will log to both the file and the DebugView window until DebugView is closed.