Serious Error

I'm just cleaning my PC from unneeded stuff, temporary files etc. I can't open everything like some exe. files. And today when I ran CCleaner, Registry Mechanic and other registry cleaners, they gave me an error that I think might have to do with some of my exe. files not wanting to open. But I don't know how to fix this error. My cleaners says it fixes it, but the next time I run the check, the same errors comes up each time. This is the error message: Missing or Invalid Key: "bwpfile\shell\open\command"
The key "bwpfile\shell\open\command", refers to an invalid command entry. "C:\Programs Files\Back Web Client\6.0.0.157L\Program\PrvCnt.exe "%""
I looked into the correct folder where this file is suppose to be listed, and when I opened the last sub folder, ""program", there was no "PrvCnt.exe" listed. How do I correct this? I don't even know what it is.

Thanks in advance for any suggestions.