If this error is not clarified/defined we are unable to provide further information. There could be many reasons causing this as there are so many components, both software and hardware, between our server and your computer.
More often than not it will be a firewall or Internet Security program configuration issue not giving JCI access to the Internet. If you can see other people online, it is likely that there is no system-wide problem and indeed the problem is local to you.
Try rebooting your computer, internet router/modem and check any program on your PC that controls what can access the Internet to ensure it is not blocking JustCamIt.
If that does not help, try using JustCamIt Lite as a backup, although this is an emergency solution and will not allow clients on mobile devices to access your chat room.