#36 HELP! Application blocked by XML error

[Alwin Bijvoet]

When on the welcome page I click 'GO' the next page
shows an XML error.
It seems that in class.template.inc the template name
is an empty string.
So the template can't be found.
It's like this:
get_template
(c:\inetpub\wwwroot\chatroom\include\templates\openchat
\.tpl): failed to open stream:... etc

This error does not occur in regulars.php but it does
in frameset.php and other pages.

PLEASE HELP!

Thanks