[TYPO3-english] Backend problems after update to 4.3.1.

[Menno Appelhof]

Hi Group,

Last week I have upgraded our 4.1 version to 4.3.1 (with the step of 
upgrading to 4.2 in between).

Everything went smooth, the frontend is working normally, it is the 
backend giving me headaches now.
When I log in on the backend the menu on the left is shown normally, the 
page tree is shown normally, but on the right side the content window is 
just showing the frontend website.

The standard Typo Mods like Template, List and Access work normally, but 
Page (with TV icont), Templavoila, News Adminand a few other just show 
the homepage on the right side of the screen.

Admin tools seem to work normally, just like the filebrowser. It is just 
a few modules under Page that don't work like they should.

The site runs on a sub-dir, htaccess which is used for RealUrl in the 
basic settings like the supplied htaccess with the typo install.

PHP version used on the server is 5.2.12, mysql is version 5.1.43.

My office system is a Mac with Safari 4.04, my other test unit is a 
Windows 7 laptop with IE8, Firefox and Chrome.

What I have tried:
- clearing browser cache; no result
- removing obosolete and beta extensions; no result
- clearing various caches in the database; no result
- clearing all temp files in typo3temp; no reult
- enabling and disabeling various extensions, clearing cache and try 
again; no result.

Any one a good idea on how to solve this problem?

Thanks,

Menno