Hiya, I am using PRTG trial version. When I am adding SNMP sensor for one of our Linux box(RHEL 5), it's giving us SNMP Error#2003. I tried both ways i.e Adding SNMP CPU Load as well as SNMP Library as recommended by PRTG but nothing worked. When I am using SNMP tester/ SNMP walk with same comunity and UDP port I am getting response for same OIDs. We have PRTG server and linux box in same vlan, so firewall is not blocking anything. Could you please tell us why PRTG is not able to communicate with Linux box?