We have several 5508 controllers, most can be remotely managed from most offices, which is useful for receptionists to access to create guest accounts. However we have one controller that can only be managed locally. Is there a security access list that could be preventing remote access?
If you try to access the web interface you just get the Internet Explorer cannot display this page message
Make sure ACL are configured correctly and its reachable from the local site and if you are able to locally configure it then only thing blocking is the ACL you can try if you can reach the port using any scanning tools also.