When clicking to edit categories get the following error :

An unexpected error has occured!

If this error persits, please report it to the administrator.

Go back to home page
Additional information about this error:
Requested category does not exist!

So I turned on debugging and got this:

Backtrace:

1. debug_die( "Requested category does not exist!" )
File: /var/www/vhosts/domaintdot/subdomains/chris/httpdocs/inc/MODEL/collections/_category.funcs.php:253
2. get_the_category_by_ID( NULL )
File: /var/www/vhosts/domaintdot/subdomains/chris/httpdocs/inc/MODEL/collections/_category.funcs.php:312
3. get_catname( NULL )
File: /var/www/vhosts/domaintdot/subdomains/chris/httpdocs/inc/CONTROL/collections/categories.php:261
4. require( "/var/www/vhosts/domaintdot/subdomains/chris/httpdocs/inc/..." )
File: /var/www/vhosts/domaintdot/subdomains/chris/httpdocs/admin.php:122

Ignored last: 1

So I looking at the database and the category does exist.

I'm using 5.0.4-10.5 , Fedora Core 4, Apache 2