Trigger of "nodata" not supported by host

[CarlosMassiah]

I have a active host that has died (I can't ssh into the thing) and my Triggers have not picked up the fact the machine has gone offline. So looking into the triggers I have found that the .nodata test which I am using are not supported. (I am testing if uptime, cpu load and hostname are not returning data).
This does not make any sense to me. Surely this is something that is entirely handled by the Zabbix server itself?
I don't need the Zabbix agent to tell me it has sent me no data...
Why would this happen?
I have attached an image, hopefully you can see what is going on.

[Pada]

The one that I use is: "{myhost:agent.ping.nodata(5m)}=1"

I have a Zabbix agent item (active) with the key "agent.ping" and an update interval of 30s, which may be too fast for some.

Triggering after only 60s may be too quick for some, especially if you want to setup dependencies so that it won't trigger when the connection between the Zabbix server and proxy went offline.

I know this doesn't explain why your trigger isn't working.
Could you perhaps tell us what version you're using and also whether all the items in that expression is enabled (and not in an unsupported state)?