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Users of FreePBX who are using version 3.5.0 or greater of DPMA and who have already Registered their FreePBX system do not need to separately execute the register utility.
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No-charge license keys for DPMA are available from Sangoma's webstore at the following web address:https://www.sangoma.com/asterisk/software/digium-phone-module-for-asterisk/
Digium Phones Module (Deprecated)
Overview
Once you have a DPMA license key, there are two primary tasks to perform in order to install DPMA software:
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