expressionengine htaccess masked cp

I'm using this htaccess for removing index.php on an ExpressionEngine MSM site http://d.pr/n/RZTo

It does what it needs but won't allow me to access the site via a masked CP (which I need for using the Mountee app.

Any ideas why I'd get a 404 when I try to hit the /admin.php for the site?

The secondary MSM site is under a sub-folder of the primary domain.

Solution

I've got a similar set up to you but in the htaccess for the second site, I don't have a rewritebase rule and have RewriteRule ^(.*)$ /index.php?$1 [L] (i.e. no reference to the folder name).

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