I have cometchat enabled for my website.
(Almost) Everybody knows that the webroot of mooSocial is served from the app/webroot folder.
If you create a directory, lets say "cometchat" within this directory you can access this via yourmoosite.com/cometchat/ (with the trailing slash at the end).
BUT,
In some cases (depending on the server/apache configuration), if you enter the same link without the slash (/): yourmoosite.com/cometchat the url will be redirect to yourmoosite.com/app/webroot/cometchat, which isn't a representing url.
To fix this issue you can add the following RewriteRules in your .htaccess file (in the root dir of mooSocial installation, not webroot):
RewriteRule ^cometchat$ /cometchat/ [L,R=301]
RewriteRule ^cometchat/admin$ /cometchat/admin/ [L,R=301]
Now yourmoosite.com/cometchat will be redirected to yourmoosite.com/cometchat/ (including the admin).
Enjoy