Upgrade issue

[donohue]

after upgrading from 5.6 to 6.0 im getting the following error:

Warning: Failed opening 'themes//theme.php' for inclusion (include_path='.:/usr/local/plesk/php/lib/php') in /usr/local/plesk/apache/vhosts/darrendonohue.com/httpdocs/header.php on line 43

Fatal error: Call to undefined function: themeheader() in /usr/local/plesk/apache/vhosts/darrendonohue.com/httpdocs/header.php on line 55

any idea's???

[hand]

It seems that the include file can't be found.

Take a look to header.php line 43.
Is there an include statement? Is this statement correct? Does the file physically exist?

Suspect ist the double slash "'themes//theme.php"