Michael Hafen wrote:

The real problem though, the 403 error, is more of a mystery.  In my experience this error is usually caused by file system permissions which don't allow apache to read and execute the perl files.  That would be the first thing to check.  If the files are owned by you, then they need to be read and executable by everyone.  On the other hand if the files are owned by www-data then the file need to be read and executable by the user.  The first case is the most likely in your case in my opinion.

It was the first case. I installed koha in root, but didn't set any permissions. Now everything works, thanks again!