On one of the servers I'm monitoring (internal netwerk, just like example 2) the status check gives back a "4" when it goes offline. When I put it back online, netXMS doesn't notice this change, I can manually poll it, edit the config through netXMS .

What can be causing this? There is no firewall and no significant change since last time it worked  ???

/EDIT
On a workstation I've just added, this is working fine ??? I am getting confused.

/EDIT2
I had a rule up in the event policy editor that said the following:

Source: [Computername] Event: SYS_IF_DOWN ALARM: [Hardcoded text] ACTION: [Send email]
Source: [Computername] Event: SYS_IF_up ALARM: [Hardcoded text] ACTION: [Send email]

When I deleted this rule, deleted the node and added the node again, everything worked perfectly, what am I doing wrong?

Example 2:

One of the printers with SNMP support i've added, when it goes offline it does not notice that the machine went offline, nor does it notice when it goes back online.  All the other DCI's via SNMP seem to be going properly and  they don't give any errors.

/EDIT
This node also has the "netXMS NAT adapter" listed as a network connection for some reason, can't find it in the documentation. Could this be the reason??

I'm using the 0.2.20 console, server and agent.