It's a Server Side Include (SSI) documents test

#include file: [an error occurred while processing this directive] #include virtual:

It's a CGI script test

#echo var:
DOCUMENT_URI=/test.shtml

#config timefmt:
Last Modified=00:08, July 26, 2013

#set var:
test_var=test_value

#if expr (apache 2.2 format):
[an error occurred while processing this directive] Add "SSILegacyExprParser on" to .htaccess

#if expr (apache 2.4+ format):
OK