Internal 500 Error -- problem with .htaccess

I have all 404 errors to redirect to my main page (which is http://www.alanwake.net/) but when I try to attempt to access an incorrect page on a subdomain, like so:

http://adm.alanwake.net/this/is/a/fake/directory

It's turns out to be a 500 error. I think what is trying to happen is that the .htaccess file is trying to redirect to the main page from that subdomain, but it has a problem and thus results in the 500 error.

vBSEO is installed in the root.

This is my .htaccess file:

Code:

# Comment the following line (add '#' at the beginning)
# to disable mod_rewrite functions.
# Please note: you still need to disable the hack in
# the vBSEO control panel to stop url rewrites.
RewriteEngine On

# Some servers require the Rewritebase directive to be
# enabled (remove '#' at the beginning to activate)
# Please note: when enabled, you must include the path
# to your root vB folder (i.e. RewriteBase /forums)
RewriteBase /
RewriteRule ^forum/(.*)$ $1 [L,R=301]
RewriteCond %{REQUEST_FILENAME} !admincp/
RewriteCond %{REQUEST_FILENAME} !modcp/
RewriteRule ^(.*\.php)$ vbseo.php?vbseourl=$1&%{QUERY_STRING} [L]

RewriteRule ^(archive/.*)$ vbseo.php?vbseourl=$1&%{QUERY_STRING} [L]

RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule ^(.+)$ vbseo.php?vbseourl=$1&%{QUERY_STRING} [L]

Is there anyway to get it ignore those subdomains?

Ahh ok I'll send my host an email now.

Isn't there anything I can do though in the .htaccess file?

I remember last time I had something similar (a simple 404 redirect) that I had change the .htaccess file to have http://www.alanwake.net/ as the url to redirect to and it worked.

Oh and http://hosting.alanwake.net/ seems to work okay.. but not the 404 error on that.

http://hosting.alanwake.net/fake/folder/