\\?\ is an unparsed path - the path is passed directly to the filesystem, bypassing checks and other Win32 API restrictions - a side effect of this is that maxi

\\?\ is an unparsed path - the path is passed directly to the filesystem, bypassing checks and other Win32 API restrictions - a side effect of this is that maximum length checks are bypassed, but this is NOT the only effect. See GP's link for more details.