403 - You're not allowed to do that.
So stop trying.
The 403 error is typically given from a webserver when you are attempting to access a file or directory whose permissions do not allow it to be read by the webserver program itself (Usually, this means it doesn't have world read on it, that is, the "other users" octal does not have the "read" bit set... well, that's at least how it is in Linux), or the file is forbidden by configuration.
This usually applies to cgi-bin directories.