Joomla White Screen Of Death Problem

[austtr]

I'm hoping we have someone on board who is experienced with Joomla problems and solutions. I’ve run into a “white screen of death” problem where a site that has been performing correctly, has now decided to go to a plain white screen when trying to access both the front-end and back-end.

I have back-ups on the hosting server and my local drive and I could reload the core Joomla files but I would much rather learn what is going on and how to fix it rather than take a "just replace everything" approach.

The following error codes are appearing in the both /public_html/error.log and public_html/administrator/error.log

Can anyone help?

Joomla ver 3.4.5
Template: Protostar

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Notice: Undefined index: ac in /home3/freigvu/public_html/language/overrides/en-GB.localise.php on line 5

Notice: Undefined index: Verify in /home3/freigvu/public_html/language/overrides/en-GB.localise.php on line 6

Notice: Undefined index: From in /home3/freigvu/public_html/language/overrides/en-GB.localise.php on line 7

Notice: Undefined index: RealName in /home3/freigvu/public_html/language/overrides/en-GB.localise.php on line 8

Notice: Undefined index: Subject in /home3/freigvu/public_html/language/overrides/en-GB.localise.php on line 9

Notice: Undefined index: MailBody in /home3/freigvu/public_html/language/overrides/en-GB.localise.php on line 10

Notice: Undefined index: MailList in /home3/freigvu/public_html/language/overrides/en-GB.localise.php on line 11

Notice: Undefined index: Format in /home3/freigvu/public_html/language/overrides/en-GB.localise.php on line 12

Notice: Undefined index: Encoding in /home3/freigvu/public_html/language/overrides/en-GB.localise.php on line 13

Notice: Undefined index: Delay in /home3/freigvu/public_html/language/overrides/en-GB.localise.php on line 14

Notice: Undefined index: SandyKey in /home3/freigvu/public_html/language/overrides/en-GB.localise.php on line 16

Notice: Undefined index: SandyNRA in /home3/freigvu/public_html/language/overrides/en-GB.localise.php on line 17

Notice: Undefined index: SandyNRB in /home3/freigvu/public_html/language/overrides/en-GB.localise.php on line 18

Notice: Undefined index: SandyRNA in /home3/freigvu/public_html/language/overrides/en-GB.localise.php on line 19

Notice: Undefined index: SandyRNB in /home3/freigvu/public_html/language/overrides/en-GB.localise.php on line 20

Notice: Undefined index: CodeSize in /home3/freigvu/public_html/language/overrides/en-GB.localise.php on line 21

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[ergophobe]

I can't help you with the specifics, but this really old post on troubleshooting PHP might help you out.

[webmasterworld.com...]

I should update it because there are some better methods these days - it's pretty easy to set up an IDE like Netbeans to allow you to set breakpoints and follow code execution step-by-step.

[austtr]

Solved....

Site was compromised. A couple of the 5 star generals over in the Joomla forums pointed me in the right direction.

[ergophobe]

Oh wow. So someone had replaced valid code with hacked code?

One tip for the future - if you set up version control, you can see this right away. For example, if you commit your site to a git repo (exempting UGC and large directories of binaries), you just type

git status

and you'll see all changed (and in this case hacked) files.

As for the binaries, there are simple shell commands that can find any file not matching certain criteria (so you can search asset directories for anything that is not a .jpg|png|gif for example