XF 2.0 Can't enter admin panel anymore

[y00sh00]

When I try to enter my admin panel I get shown an error "An unexpected error occurred. Please try again later." If I look in the database what the last error is that is thrown I see:

message: The session key must be overridden.

The stack trace:
#0 src/XF/Container.php(28): XF\App->XF\{closure}(Object(XF\Container))
#1 src/XF/App.php(2199): XF\Container->offsetGet('session')
#2 src/XF/Admin/App.php(52): XF\App->session()
#3 src/XF/App.php(1876): XF\Admin\App->start(true)
#4 src/XF.php(328): XF\App->run()
#5 admin.php(13): XF::runApp('XF\\Admin\\App')
#6 {main} | a:4:{s:3:"url";s:16:"/forum/admin.php";s:8:"referrer";s:46:"https://www.pandemic-horde.org/forum/index.php";s:4:"_GET";a:0:{}s:5:"_POST";a:0:{}}

I'm not quite sure when to start on analysing fixing this myself as I'm not quite sure what this means. I've tried to figure out where this exception is thrown but only see a reference in XF\App.php

Could someone provide me with a little bit more context? This is currently occurring on a production environment that has not had any issues in the past and im recovering a backup to my dev environment to maybe debug some more.

Any insight would be greatly appreciated.

 

[Mike]

At a base line, it might be worth re-uploading the files and/or restarting the web server (or PHP-FPM). Either PHP isn't executing the code as written or for some reason, code is missing. I can't really see what else it might be.

If you're running PHP 7.3.0 specifically, there is a bug in that which might be relevant. 7.3.1 is available with a fix.

 

[y00sh00]

I will double check, but if I am running 7.3 I am expecting much of my own tools and code to break. Before I saw your reply I checked restoring a backup to a dev environment and that all works fine. So it does indeed seem to be file or server related. I'll schedule a restart for Monday or so and have another look. If that doesn't work I'll re-upload the files or restore them from a later backup.

Thank you very much for the quick reply!

 

[y00sh00]

Would just like to respond and say that a reboot of web server did indeed solve the issue. In case anyone ever stumbled upon a similar issue.