Moved blog to new domain within same host

I only used MyQuickDomain-account to move the hosting plan to my new domain name….before I made any changes IN wordpress… So ever since then I’ve been having problems.
It seemes I’ve tried every tips and tricks with FTP and MyPHP for correcting this issue.

think I’ve read all the wordpress docs about “moving wordpress” to.
The site was up for a short time, but I couldn’t access my admin, and now I only get “500 error”