Question : enable authentication required for SMTP

Dear experts,
I have 2 domino mail cluster, now I Enable authentication required for SMTP. But user can not  login into server 1 to send email  to user have mailbox on server 2

Error transferring to SERVERMAIL2; SMTP Protocol Returned a Permanent Error 530 Authentication required

Pls help us to solve this problem.

Thanks,
VinhBT

Answer : enable authentication required for SMTP

I have a test-situation in which SMTP allowed within the local internet domain is set to Disabled.

Can you try that?