Directives in httpd.conf under VirtualHost must include the subdirectory information:
RewriteEngine On
RewriteRule ^/subdir/(.*):(.*) /subdir/index.php/$1:$2
Directives under <Directory "D:/path/to/directory"> did not do the job for escaping semicolons.
By the way, thanks for the great job, very clear explanations and simple code to use.
I was struggling for years with this one on several wikis installed on Windows server and Apache.
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