With the new Joomla! 2.5 out, it was time to upgrade my Joomla! 1.7 installation. You have the option to upgrade with a single click but before you do press the button, I advise you to try it on a local copy of your website. It was a smart move to follow when I did the upgrade, after which I was confronted with the scary HTTP 500 (Internal Server Error) message in Google Chrome, whereas in Firefox I get an empty screen.
Confronting with the error
My first reaction was to login into the back-end and check if everything was ok. But to my surprise, when I clicked the Global Configuration button I was confronted with the same scary HTTP 500 error. I then tried to add an article or category, which gave me the same error.
Searching for the solution
It was a natural choice to look up the error on Google. After some forum posts which described that the cause could be wrong file permissions, I was at the exact same place with a non-working website.
I then discovered a post from Brian Teeman on his blog - Upgrading to Joomla 2.5 - Some Warnings. It is a great tutorial for everyone who is having troubles when upgrading to Joomla 2.5. Unfortunately the steps did not solve my problem.
I then tried to disable all 3rd party plugins but after I wanted to open the plugin settings I got the server error. So the only option that was left, was to:
- Reinstall the working 1.7 version,
- Disabling all of the 3rd party plugins,
- Upgrading to version 2.5,
- And voila, it worked perfectly.
So which plugin was the root of the error? It is the Phoca Gallery Plugin, ver. 3.1.2. Now the funny thing is, that if I enable the plugin my page stops working and after that you cannot disable the plugin in the administrator. If you try to get access to the settings of the plugin you get the HTTP 500 error. So the only option to disable the plugin is to go into the database and manually disable it. The table that you are looking for is
yourTableSuffix_extensions with the row
plg_content_phocagallery. You now need to change the value of the field enabled from 1 to 0. Of course you wont be able to use the gallery until the plugin is fixed.
If you do not have Phoca Gallery installed and you are having the same problems, you can disable the plugins to narrow down the list of suspects.
I hope it will help others with the same problem.