Codezwiz >> Forums >> General PHP Nuke Help >> Problems with Numerous Header Errors

Well, I am just getting into php-nuke, and already i have hit numerous snags.

I just installed a 7.8 fileset and accompanied it with a flash navigation block.
every time i now try to use an administrative command i get a blank white page with something along these lines on it:

Warning: Cannot modify header information - headers already sent by (output started at c:\websites\admin\godzarmy\www\nuke\html\admin\case\case.flashnav.php:1) in c:\websites\admin\godzarmy\www\nuke\html\admin\modules\flashnav.php on line 67

substitute "flashnav.php on line 67" for any number of module .php pages. I am not sure waht is going wrong.
If it is related, i also have a series of errors that read banner errors:

Warning: main(banners.php): failed to open stream: No such file or directory in c:\websites\admin\godzarmy\www\nuke\html\themes\TechraDark\footer.php on line 21

Warning: main(): Failed opening 'banners.php' for inclusion (include_path='.;c:\php\includes') in c:\websites\admin\godzarmy\www\nuke\html\themes\TechraDark\footer.php on line 21

these appear for any theme, not just the one i am using.

please help determine the problem, and try to keep the solution in VERY simple terms, i am very new to this!
thanks if you can help!
~SoL