Aastra 6755i User Manual page 237

2. The "UPnP Mapping Lines" field is set to 0 by default. If required, change the setting to a
specific line by selecting a line from the list. Valid values are 0 through 10. The line you select
is the line that your remote phone uses to perform Universal Plug and Play on the network you
are connecting to.
3. Click
Model 6755i IP Phone User Guide
to save your settings.
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