MyBB Community Forums

I am not sure what i changed but now no matter what plug in i attempt to install i get 

The page you are trying to access is restricted due to a security rule.

If you believe the security rule is affecting the normal operation of your website, contact your host support team and provide detailed instructions how to recreate this error. 
They will be able to assist you with rectifying the problem and adjusting the security configuration if needed.


When I hit submit after install
Any clue what i messed up?

if server error log or killed tasks exist at your web host panel then check recent entries of the log.

or better to contact web host & ask what is wrong with the plugin uploader plugin files (provide them the plugin files)

Edit: do you use .htaccess file for your forum ? (assuming that you are using Apache server)
if so check whether it has below rule. if it doesn't exist then add it and check if it helps.

<IfModule mod_security.c>
# Turn the filtering engine On or Off
SecFilterEngine Off
</IfModule>

adding that to my htaccess fixed it, thank you.