Permalinks

Hi guys, I’ve recently added a blog back to my site and I’m just trying to set it up http://jamesduffell.com

I use to use custom permalinks however they’re suddenly stopped working, and simply give me the 404 error.

I know it’s not my hosting as I host several other websites which are located in sub folders and these work fine, it’s simply my main site located in the top level which has this issue.
I’m using the follow in my htaccess file, which seems to work fine for my other sites for example http://handyseo.co.uk

ErrorDocument 400 http://jamesduffell.com
ErrorDocument 401 http://jamesduffell.com
ErrorDocument 403 http://jamesduffell.com
ErrorDocument 404 http://jamesduffell.com
ErrorDocument 500 http://jamesduffell.com

# BEGIN WordPress
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>
# END WordPress

Just not my main site.

If anyone can point me in the right direction or has encountered this before it would be great to hear from you.