Unable to edit site in any way (add users, edit content, ...)

@Hans, I have two ideas:
1) Disable the overlay and try again.
2) Look in your error logs to see if there are hidden errors that you aren't seeing.

@saintiss: The PHP error logs are provided by your web host.

Hello, i just had the exact same problem after copying a drupal installation to another server:

Symptoms:

- Website works perfectly in read-only.
- Can authenticate as an admin fine.
- Overlay is not working: firebug net tab is saying the url called sends an error 404, then i'm redirected to a version of the edit that's the same as if i didn't have javascript enabled.
- No change can be saved, be it articles or website configuration, including disabling of overlay.
- No error is reported by the website itself.
- Apache/php logs aren't showing much, except rare errors like this:

[Fri Aug 05 11:09:50 2011] [error] [client 62.72.x.x] File does not exist: /home/www/Drupal/mySite/node, referer: http://mysite.example.com/

More infos:

- It should be noted that i all i did was copy a website that was working fine from one server to another (sources + database). It worked fine on the first server, but not on the second.
- I know it's not db related, since i configured the same database on a working instance and the faulty one, without changes.
- All the files of the faulty drupal install have been recursively set with a 777 permission, so this shouldn't be a permissions related issue.

Any ideas?

Apache configuration issue, either from httpd.conf, VirtualHost configuration or .htaccess. If AllowOverride is set to None, Apache won't take .htaccess files into account.

@mvreux: it looks like your new webserver is not working with clean urls (i.e. http://yoursite/node won't work but http://yoursite/?q=node does). Did you remember to copy /.htaccess? It's a hidden file. Otherwise your server needs to be configured to read this file.

Thanks for swift answers! :)

The .htaccess is indeed there (other wise, i could only access the homepage of the website),
Clean urls are working, since i can access pages like /node/60 and also the ones with a pathauto url, like /content/my-rewritten-url
My virtualhost file seems to be fine, it looks like this:

<VirtualHost *:80>
ServerAdmin mvreux@mysite.com
ServerName mysite.example.com
DocumentRoot /home/www/Drupal/mysite
<Directory /home/www/Drupal/mysite>
        Options Indexes FollowSymLinks Multiviews
        AllowOverride All
        Order allow,deny
        allow from all
</Directory>
ErrorLog /var/log/apache2/mysite-error.log
LogLevel debug
CustomLog /var/log/apache2/mysite-access.log combined
</VirtualHost>

I compared the config files apache2.conf et ports.conf, no difference. /etc/apache2/httpd.conf is empty for both the working and broken drupal.

Did you check that your file-system settings are suitable to the new web-server? Temporary directory in particular, as well as public/private files.

I found the problem! It seems the rewrite module from apache ( mod_rewrite ) wasn't activated...which is kinda weird, since it looked like it was already activated: all pages with a rewritten url like http://mysite.example.com/mypage were working already!

Fixed then ?

Hi,
So how did you activate that module?

Thanks.