WHMCS's mail provider sends invoices, welcome messages and support notifications. Configure it independently from support-mail importing, using the authenticated sending method approved by your mail provider.
01 Configure SMTP delivery
- Obtain the provider's correct SMTP hostname, port, encryption mode, username and authentication requirements.
- Open General Settings and Mail, then choose Configure Mail Provider.
- Select the SMTP configuration and enter the approved connection details. Match the port and encryption mode to the provider's instructions.
- Use Test Configuration and resolve authentication, certificate or network errors.
- Save, then send controlled examples of an invoice, product welcome message and support reply.
- Verify receipt, sender identity, reply address and links at the destination mailbox.
02 Use the provider's supported authentication
Some mail services require a dedicated application method or OAuth-based integration instead of an ordinary mailbox password. Follow the current WHMCS provider guide for that service. Do not weaken the mailbox's authentication policy to make a generic SMTP example work.
Confirm that the provider permits each configured From address, including support departments. A successful test from one sender does not prove that all department identities are authorised.
Common questions
Does SMTP setup import customer replies?
No. Configure support email importing or piping separately for inbound messages.
Does Test Configuration prove inbox delivery?
It confirms the tested submission path. Check the actual destination and provider delivery events because later rejection or filtering can still occur.
How should staff collect a useful error?
Enable the mail provider's Debugging option briefly, reproduce one controlled failure and inspect System Logs. Keep output private and disable debugging afterwards.
After changing credentials or moving WHMCS, retest the connection from both web actions and scheduled messages. Differences in PHP configuration or outbound network policy can affect one path while the other continues to work.