I have been trying to get rdiff-backup to work under these constraints:
* source files are on a local disk on Windows 7
* the backup is to be stored on a network share (mounted as a Windows drive letter)
I first tried this with the Windows-built executable (1.2.8 and 1.3.3), but both have issues with long file paths (and I don't believe that "just don't use long file paths" is a reasonable workaround).
I then tried using the version included with Cygwin (1.2.8-5), but it gets this error, again when backing up to a remote shared drive folder:
OverflowError: group id is greater than maximum
I tried to hack the Python code and just remove the offending line (rpath.py:977) (it seemed reasonable to try it), and then I got an error about an inode key not being found -- maybe related to hardlinking not being allowed on network shares?