Mit include Teile von Webiste auslagern

[Beat]

keiner eine Idee? und bitte nicht wieder auf Suchfunktion verweisen

Kann es sein, dass für das betreffende Verzeichnis SSI gar nicht eingeschaltet ist?

Ich zitiere von hier
http://httpd.apache.org/docs/2.0/howto/ssi.html

Configuring your server to permit SSI

To permit SSI on your server, you must have the following directive either in your httpd.conf file, or in a .htaccess file:

Options +Includes

This tells Apache that you want to permit files to be parsed for SSI directives. Note that most configurations contain multiple Options directives that can override each other. You will probably need to apply the Options to the specific directory where you want SSI enabled in order to assure that it gets evaluated last.

Not just any file is parsed for SSI directives. You have to tell Apache which files should be parsed. There are two ways to do this. You can tell Apache to parse any file with a particular file extension, such as .shtml, with the following directives:

AddType text/html .shtml
  AddOutputFilter INCLUDES .shtml

mfg Beat