Here are some pages on each of those errors. They are both server problems that you may need to contact your host to fix.
MySQL Server has gone away:
This is a server issue. See this:
http://www.vbulletin.com/docs/html/t...mysql_goneaway and this:
http://www.vbulletin.com/forum/showt...265#post310265
MySQL can't connect (through socket):
See this page for the causes of this error:
http://www.vbulletin.com/docs/html/cantconnect