Failed opening required file

I know the problem is to do with the path location as stated in other threads...

My file has:
require_once("DB.php");

My php.ini file has:

;***** Added by go-pear
include_path=".;c:phppear"
;*****

And I have c:phppear with all the relevant files in the correct location. I ran a registry file too.

My error message is:
PHP Fatal error: main(): Failed opening required 'DB.php' (include_path='.;c:phppear') in C:blahtest.php on line 3

In the php info page I get:
include_path .;c:phppear for local value and master value.

Any ideas? Thanks, Kevin