htaccess rewrite

hi
I've been using this rewrite and it works fine but now I'm using a subdomain so things are getting redirected inappropriately, please advise how to have non www redirect to www., but excluding a specific subdomain

RewriteEngine on
RewriteCond %{HTTP_HOST} !^www\.domainname\.com$ [NC]
RewriteRule ^(.*)$ http://www.domainname.com/$1 [R=301,L]

Thank you

 

The following code will redirect the non www request coming to your main website to www of the main website.

This won't affect the sub-domains.

 

Thanks for the suggestion but this results in the following message from http://subdomain. or http://www.

Firefox has detected that the server is redirecting the request for this address in a way that will never complete.

or
Safari can’t open the page.
Too many redirects occurred trying to open “http://www.domainname.com/”. This might occur if you open a page that is redirected to open another page which then is redirected to open the original page.

However http://domainname.com works.

Thanks

 

Try this,

Options +FollowSymLinks
RewriteEngine on
RewriteCond %{HTTP_HOST} ^domain\.com
RewriteRule ^(.*)$ http://www.domain.com/$1 [L,R=301]

 

Awesome, this works perfectly, thank you esupportsnet