I'm aware that Windows 7 is rather persnickety about the C drive. Aside from being an overall bad move to store things directly on the root of C, it is very protective of this location.
However, having said that, I do see you also followed that with <path>, which would seem to infer that you have an actual folder off the root of C. And that should be perfectly permissable. Advisable even. That's how I work myself as well as suggesting it to class participants when I facilitate RoboHelp classes.
You might want to ensure that you have total ownership of the folder. You might want to investigate Ultimate Windows Tweaker.
Helpful and Handy Links
Could it also be a robohelp version issue? From memory, RH8 is the first supported for Vista/Win7, so maybe if an earlier version is being usedyou might encounter problems?
I have the exact same issue since upgrading to Windows 7. I am using RH 9.
Have you found a solution?
I have the exact same issue since ugrading to Windows 7. I am using RH 9. My project is stored in a folder off the root of C.
This does not happen with every topic, and does not always happen to the same topic again.
In addition to what Rick suggests, could this be a problem with Windows' User Account Control (UAC)? You can try disabling UAC. (If your IT department allows it. It may expose your computer so do so at your own risk.) Simply moving the project to a different local drive should solve all UAC related problems.
Surely if it was a UAC problem it would happen all the time? It only happens occasionally, and not with all topics.