Ubuntu - Permission denied when trying to run amportal a ma installall

We followed this step by step tutorial, but installed asterisk1.8 instead of 11 (because there was some module incompatibilites).

Now we have the following two problems:

When executing amportal a ma installall, following error messages appears:

/var/lib/asterisk/bin/freepbx_engine: line 484: /var/lib/asterisk/bin/module_admin: Permission denied

As we understood, at this point of the installation we should be able to access the web interface via /admin, but trying to open this destination results in a 404 not found. Accessing only the shows a default html-file saying “It Works!”.

We have noticed that apache2 is run by user asterisk and user root, but freepbx only by user root. Might this be a problem?

Sysop Edited title by SK