Hello Devin Young !

It looks like not upgraded .htaccess file. Please check - does it has the following code within:

    RewriteCond %{REQUEST_FILENAME} -f [OR]

    RewriteCond %{REQUEST_FILENAME} -d

    RewriteRule .+ - [L]

    RewriteRule ^(.+)$ r.php?_q=$1 [QSA,L]

?