If you log into the web interface
then to:
System Administration Tool
then at the top left choose:
Maintenance and Diagnostics
then:
IP Telephones
then:
All IP Telephones
that will show you which phones are programmed, and whether the Mitel can see them (in Service)
it won't show if they are on a call etc
Out of service means the Mitel 3300 cannot see that phone, at that time
Neil, Converged