zabbix stopped monitoring when i'm adding new hosts

[asp]

zabbix 2.0.3
I add about 40 hosts that are monitored using snmpv2, after this i see this (look pic). I was changed icmppoller

File: /usr/local/etc/zabbix_server.conf

### Option: StartPollers
# Number of pre-forked instances of pollers.
#
# Mandatory: no
# Range: 0-1000
# Default:
StartPollers=50

and the same i did it in /home/username/zabbix-2.0.3/conf/zabbix_server.conf

What I didn't change yet? What's wrong?