TYPO3 Admin Panel Not Working Properly

Backend
1

I’m having a strange issue with my TYPO3 installation and wondering if anyone can help me out.

Starting from two days ago, the admin panel on one of my TYPO3 websites stopped working correctly. I can still log in without any problems, but as soon as I click on any option from the left navigation menu, everything breaks down completely.

What happens is that the interface gets messed up - additional menu panels start appearing and overlapping each other. At first, there was just one extra menu, but when I kept trying different functions, even more panels showed up.

Occasionally, I get this error message:

“Tree structure error - Received unexpected server response. Check system logs for more information.”

The problem is I cannot get to the logs because the whole backend is unusable.

I already tried clearing my browser cache, opening the browser in safe mode with all extensions disabled, and even logging in with a different user account. Nothing helps and I always get the same broken interface.

Anyone know how to fix this? Other users seem to be able to use the site normally, so it looks like this is not affecting the entire installation.

2

It appears you might be dealing with a caching issue in TYPO3, which can cause the backend to misbehave after updates. I’ve encountered similar problems, and one effective solution is to access your server via FTP or SSH and clear the contents of the typo3temp directory, particularly the var/cache folder. If issues persist, consider checking the be_sessions table in your database through phpMyAdmin, as outdated session entries can lead to various conflicts. Always remember to back up your data before making any changes.

3

that’s super weird! have u tried accessing the backend from a different device or network? sometimes it’s not just the browser cache - could be a session issue or something with your network. also, what version of TYPO3 are u using?

4

sounds like javaScript conflicts or corrupted backend files. try uploading fresh TYPO3 core files from your version - just overwrite the typo3/ folder (not typo3conf!). had a similar overlapping menus issue last year and this fixed it completely.