I have numerous sites on a reseller account and today installed a fresh site only to be unable to install MaxiGallery snippet - I went back to some old sites and tried to duplicate the snippet and those too would not allow me to either which obvioulsy pointed to Hosting issues, further searches and this thread
http://modxcms.com/forums/index.php/topic,53447.0.html still did not resolve the issue.
So contacted the guys at KNet and after a couple of hours they’ve resolved the problem - so if you’re having any similar issues it could be down to your hosting provider installing security patches affecting Mod Security .
This from one of the guys
We periodically update our Mod Security rules to make sure we are protected against the latest hacks, unfortunately they do flag a few false positives from time to time!
