Yealink SIP-T2 SERIES Administrator's Manual page 351

Parameters
Description:
Configures the anonymous call rejection off code to deactivate the server-side
anonymous call rejection feature for account X.
X ranges from 1 to 16 (for SIP VP-T49G/SIP-T48G/T46G/T29G)
X ranges from 1 to 12 (for SIP-T42G)
X ranges from 1 to 6 (for SIP-T41P/T27P)
X ranges from 1 to 3 (for SIP-T40P/T23P/T23G)
X ranges from 1 to 2 (for SIP-T21(P) E2)
X is equal to 1 (for SIP-T19(P) E2/CP860)
Example:
account.1.anonymous_reject_offcode = *75
Note: It works only if the value of the parameter
―account.X.send_anonymous_rejection_code‖ is set to 0 (Off Code).
Web User Interface:
Account->Basic->Send Anonymous Rejection Code->Off Code
Phone User Interface:
Menu->Features->Anonymous Call->Reject Off Code
To configure anonymous call rejection via web user interface:
1. Click on Account->Basic.
2. Select the desired account from the pull-down list of Account.
3. Select the desired value from the pull-down list of Local Anonymous Rejection.
4. Select the desired value from the pull-down list of Send Anonymous Rejection
code.
5. (Optional.) Enter the Send Anonymous Rejection on code in the On Code field.
6. (Optional.) Enter the Send Anonymous Rejection off code in the Off Code field.
Configuring Basic Features
Permitted Values Default
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