I work at a web design agency (WordPress), and all of our websites link back to our own site credits in the footer. However, our security plugin adds a line in the .htaccess file that blocks all requests that do not specify a user agent in order to prevent bots with a 403 error like this:

RewriteRule ^.* - [F,L]

This is fine for the sites we still manage, as we simply added a user agent into the request. However we have some ex-clients that we don’t host or manage anymore, and those requests are being blocked because they have no user agent and we have no way of adding one anymore. Is there a way I can add something to our .htaccess that whitelists these URLs so they can make the request without a user agent?

I’ve tried adding various http headers and a few other things (it’s been a while I can’t remember), but nothing worked.