Thread:Project:Support desk/Can't contact the database server: Access denied for user 'wikiuser'@'localhost' (using password: NO) (localhost))/reply (5)

Those settings seem okay.

Maybe the problem is the user. Note that on mysql the user is also associated to a host (localhost in this case). Try resetting the password: http://dev.mysql.com/doc/refman/5.0/en/assigning-passwords.html

You should do that for 'wikiuser'@'localhost', 'wikiuser'@'%' and 'wikiuser'@'yourhost', where "yourhost" is the hostname of the database.