mortenoc

No, it was not a user/password issue. But I found an explination – and more important a solution – here:

http://markjaquith.wordpress.com/2006/03/28/wordpress-error-you-do-not-have-sufficient-permissions-to-access-this-page/

Note that the force-upgrade.php is to be run after uploading the files
of the new version.

regards
Mortenoc

Well. After closing firefox and opening it again everything was all right again.
I have no idea what happened.

Thanks
Morten