Altigen AltiView Manual page 52

the order from Forwarding Number 1 through Forwarding Number 4.
Note that this number order does not correspond to the Schedule
order—Forward Number 2 is not used first during Schedule Number
2.
Note: If your system administrator has disabled the Check Password
option for your ONA settings, a call forwarded via ONA that is
picked up by a voice mail box, fax machine, or answering machine
will connect, and will not try any subsequent Forwarding
Numbers. Therefore, if you want ONA to use such an option as a
"last resort," it should be Forwarding Number 4.
You can set the ONA ring duration from 5 to 45 seconds using the Ring
for ... seconds drop-down list. Default value is 20 seconds. The system will
ring the ONA target within the specified time limit. If the ring time exceeds
30 seconds, the system will play a phrase every 15 seconds (playing time is
included in ring time).
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