RDC 10.8.2 Permissions Error

When I try and use the RDC (2.1.1) on OSX 10.8.2, it starts up, then says,

"Cannot open Macintosh. Make sure the file exists and you have permissions to read the file."

It then goes on to say it doesn't have permissions to open a temp file, something along the lines of,

"Cannot open 838372.tmp. Make sure the file exists and you have permissions to read the file."

Any solutions?