for some reason all my php sites running at the server are giving
Premature end of script headers:
what might be causing this? although phpinfo() is working just fine
and normal echo "example"; tags are also working but not the one that needs mysql etc.. such as vbulletin
Did this happen after a Cpanel update? Did you just get a new website and you are trying to install Vbulletin on it and it's not working? Some more history is important. Are you an admin (with WHM access) or are you a reseller / end user who just happen to be coming to Cpanel forums thinking it's a cpanel problem?
If your server is running phpsuexec, check /usr/local/apache/logs/suexec.log and see what it says when you call one of those scripts. Also check /usr/local/apache/log/error.log . Also check error.log or error_log in the web directory where your php is running. All of those should give you some clue what is going on.
Do your PHP pages end in .php ? .php3 ? .phtml ? or something else?
If your server is running phpsuexec, make sure that your php files are not chmod'd 755 or they will not work. They should be chmod'd 644. Make sure your directories are chmod'd 755 or more restrictive - no directories or files chmod'd 777.
Mike