Aastra Dialog 4187 Plus User Manual page 20

Incoming Calls
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To restore Parallel Ringing
Lift the handset.
Dial.
Note: U.K., dial
Replace the handset.
Notes:
If you want to restore Parallel Ringing for all phones defined
in the list, follow the procedure for restoring the feature from
the phone with the main extension number and enter the
number of the answering position.
If you want to restore Parallel Ringing for one specific phone
in the list only, follow the procedure for restoring the feature
from this phone and enter its extension number.
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Dialog 4187 Plus