[Solved] PHP Error was Encountered

I am receiving the following error on the site, everything seems to be working I was able to setup the installation despite this error.

A PHP Error was encountered

Severity: Notice
Message: Only variable references should be returned by reference
Filename: core/Common.php
Line Number: 257

It’s not an error, it’s a notice that something in Codeigniter (core directory) does not match the PHP standards. But this is nothing we’ll patch or fix.
If your webserver displays these messages you should take a look at this: http://www.cyberciti.biz/faq/php-stop-notice-variable-warnings-errorlogs/

I get this error too if I use PHP 5.6.4, if using anything older than 5.6 this error no longer shows up.
If possible try using PHP 5.5.x

Edit the file at the mentioned line. I fixed it by putting the returned value in a variable first and THEN return the value. I don’t know anymore what the code exactly was, but it was something like this:

return config[0] &= configwhatever;

Change this to

config[0] &= configwhatever;
return config[0];