I recently upgraded my mythbuntu installation from 12.04 to 14.04. For some reason the distribution upgrade tool failed on me. I had to upgrade manually by updating everything in /etc/apt/sources* to point to trusty instead of precise.

After a reboot I was surprised to find out that everything upgraded beautifully except for one thing – mythweb. When I tried to start Apache I was greeted with this lovely message:

* The apache2 configtest failed.
Output of config test was:
AH00526: Syntax error on line 30 of /etc/apache2/sites-enabled/mythweb.conf:
Illegal option AllowAll
Action 'configtest' failed.
The Apache error log may have more information.

It turns out Ubuntu 14.04 uses a different version of Apache with different syntax, which breaks the configuration. Thanks to this post I found the fix to be relatively easy:

sudo rm /etc/apache2/sites-available/mythweb.conf
sudo dpkg-reconfigure mythweb
sudo /etc/init.d/apache2 start

After that was done, all was well and upgraded.