Debugging Gmail Relevant issue in Email Settings


Yeastar S-Series IPPBX support use external SMTP server and POP server to sending and receiving Email. Gmail is a worldwide famous Email Exchange service provider and compatible with Yeastar PBX. With Gmail, we can easily use the feature below in Yeastar PBX. 

  • Voicemail to Email
  • SMS to Email/ Email to SMS
  • Fax to Email
  • Retrieve the Admin password

While you might encounter the failure during test and normal operationw with Gmail account.

This guide mainly share a common procedure to debug Gmail setup in Yeastar S-Series IPPBX.

In this guide, you would  need to login to the SSH for command running. Refer to the guide How to log in SSH of Yeastar S-Series IPPBX

Step 1. Make sure PBX access to Internet

Try to PING or DNS resolve the Gmail SMTP server. 

If failed, please check the network connection of the PBX. 


Step 2. Check the SMTP/POP settings

Refer to guide SMTP Settings for Gmail

SMTP Server address: (TLS Port 587)

POP3 Server address: (TLS port 995)



Step 3. Enable the Option "Allow less secure apps: On"

Refer to the explain from Gmail Allowing less secure apps to access your account

Input this link to your browser and enable the option. 


Step 4. Enable the POP and IMAP

Input link in browser to reach gmail setting page and enable the POP Download and IMAP Access



Step 5. Run ssmtp debug and some typical errors.

Under the SSH, run the command 

ssmtp -D /ysdisk/etc/mailbox/sysmail -vt </ysdisk/support/tmp/testsysmailbox.eml 

to see the debug details. 

Here are several typical errors as below.

  • ssmtp: Cannot open 

This may caused by the router/firewall secure policies has enabled the restriction to SMTP port 587.

  • Error code 530 5.5.1


This error means Password Authentication needed. Setting in Yeastar PBX as below.

  • Error: send-mail: Authorization failed 534 5.7.14

This problem may caused by the gmail account has been locked out due to many 3rd party less secure apps tried to log in this mail account, use this link and click CONTINUE to unlock this account. 







Have more questions? Submit a request


Please sign in to leave a comment.