It's almost impossible to say, given the limited data available, but there are many possibilities.
The fact that the web service starts manually but 'with the wrong root directory' implies you have multiple Apache installations. Did you manually install your own web server setup? If so most bets are off.
Second to that, have you tried stopping the web server via serveradmin (sudo serveradmin stop web). It may be that ServerAdmin isn't noticing the fact you killed and restarted Apache while it wasn't looking, so telling it to stop might help.
Beyond that, what do the logs say?
We can repeat the problem on a new Mac Mini.
Run Mac OsX Server 10.8.2 and start Server App.
Enable/Disable WebSites service and everything works fine (Switched on we can access to web server page "Server" and switched off the web server is off).
Then we close WebSites Services and we close Server App.
Check in Activity Monitor and see httpd process running (why?).
Then kill httpd process in Activity Monitor.
Open ServerApp and starts WebSites Service. It doesn't start.
No additional info in /var/log/apache2/access_log
No additional info in /var/log/apache2/error_log
It is the same behaviour of the other MacMini Server.
They are new Mac Mini Server with preinstalled release.
We don't install anything.
On both two Mac Mini:
sudo apachectl -k start
The web server starts and we can see the web page "It works" (it is not the "Server" web page, it has a different root directory)
sudo apachectl -k stop
The web server stops
sudo serveradmin start web
web:state = "RUNNING"
The webserver doesn't start
No new info in access_log and error_log
What can we check?
How can we "reset" the webservices?
How can we see additional report?
I have the exact same problem, althouth PHP doesn't seem to be the issue. I have tried everythin else (re-installing Server.app etc) with no luck. The command you suggested produces the following:
sudo ln -s libpq.5.4.dylib libpq.5.dylib
ln: libpq.5.dylib: File exists
The /usr/lib has the following relevant entries:
-rwxr-xr-x 1 root wheel 163840 Sep 13 23:23 libpq.5.4.dylib
lrwxr-xr-x 1 root wheel 15 Nov 16 2012 libpq.5.dylib -> libpq.5.4.dylib
lrwxr-xr-x 1 root wheel 15 Nov 16 2012 libpq.dylib -> libpq.5.4.dylib
Could you please help?
BTW, in our case we never touched the Websites configuration. When I wanted to activate it, it never started.
Thanks in advance