Hey Marius thank you very much for the reply!
I checked and matched the database name together with the one in the wp config file.
I wouldn't have some rights to write, interesting, strange because I own the domain so everything should be open for me.
How can I update the PHP version or check if the htaccess is legit?
Thanks again, I'll try to move to another server if it doesn't work.
P.S. Any news about the infamous 1und1 problem, if it had been fixed?