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If you have a windows server, you cannot run php on those pages. You need a Linux server for this. This means you cannot put PHP in a subdirectory or folder. They are correct that it would have to be a subdomain, hosted on a linux server. You can redirect a URL from your subdomain to a subdirectory URL, but if the content is in php, you cannot put the same content from the subdomain into a subfolder. Using a subdomain is not the end of the world. It is not ideal, but it won't kill you. Your best bet would be to try and change your hosting to be on a linux server, then use a subdirectory. If not, you have no choice really.