Update the saved PD Azure SMS connection string when the resource access key changes or you are moving to the intended credential for the same resource. Keep the sender and endpoint association under review while doing so.

Before starting, read the Azure SMS eligibility guide and confirm that your existing Azure resource and sender remain suitable.

Prepare the credential change

Have the Azure resource administrator review which key and connection string this gateway uses and which other applications use that key. Azure resources have primary and secondary keys with corresponding connection strings. Regenerating a key invalidates credentials based on that key; changing an unrelated key is not a repair for a sender refusal.

Use Microsoft’s key-management guidance and your approved rotation process. Keep a supported working credential available during the transition where appropriate, and coordinate other applications before retiring the old key.

Update the saved gateway

1. Open PD Modules → Azure SMS → Gateways.
2. Configure the intended Azure gateway and check its label and From sender.
3. Replace Connection string with the complete current value from that same resource’s Keys page.
4. Use the saved secret field’s replacement control where offered, then choose Save gateway.
5. Run Test connection and read the full result.

Replace the whole connection string rather than combining a new endpoint with an old key. A saved or masked field is not proof that the replacement value was entered and saved successfully.

Confirm operation separately

The connection check has no recipients. Sender readiness, destination eligibility and delivery still need their own review. A Log only rehearsal cannot validate an Azure key because it makes no Azure request. Use normal intended operation or a deliberately approved real test when confirming live delivery.

If a send fails after the change, review the resource, sender and original error rather than rotating repeatedly. An uncertain timeout may already have reached Azure; reconcile that attempt before another send.

Do not include the old or new connection string, access keys or private client data.

See the PD Azure SMS WHMCS guide for related tasks, or explore PD Azure SMS.