with (www) on url i get download file!

[tec]

I have a site that i have registered recently, when i open the website "http://www.example.com" i got a popup says download file! however; if i type "http://example.com" without (www) the site loads correctly.

Could it be a cache problem?

Examples:

typing this loads the page correctly
http://www.site.com/index.php
http://site.com/

However; doing this:
http://www.site.com/

i get a request to download the file which contains the code of my index.php file.

[rcgreen]

The name server is configured incorrectly. Do you
control it yourself or does someone else?

[tec]

The name server is configured incorrectly. Do you
control it yourself or does someone else?

I do control it

[rcgreen]

Are you running bind? If so, could you
post the configuration files?

[tec]

Are you running bind? If so, could you
post the configuration files?

Sorry rcgreen but am not expert in this, but did you mean /etc/named.conf?

[rcgreen]

Yes, and named.conf will reference some other
files that contain zone information.