Error after Login

[ChrisSeiler]

Hello
I just installed webERP on my webserver. I set the admin password and tried to log in, but I only get the following error.

Warning: mysqli_connect(): (HY000/2002): No such file or directory in /kunden/351322_8001/web/2039205/A2039205/www/webERP/includes/ConnectDB_mysqli.inc on line 17

Warning: mysqli_set_charset() expects parameter 1 to be mysqli, boolean given in /kunden/351322_8001/web/2039205/A2039205/www/webERP/includes/ConnectDB_mysqli.inc on line 23
Connect failed: No such file or directory
Click here to try logging in again

I changed the port in Connect_DB files to the one used for the MYSQL database amd tried with changing mysqli to mysql in the config.php page, but then i get another, similar, error. Is there anything else I coudld look for to make it work?