Issue connecting Zoho Mail to Thunderbird (IMAP/SMTP authentication error)

Issue connecting Zoho Mail to Thunderbird (IMAP/SMTP authentication error)

Dear Zoho Support,

I am trying to configure my Zoho Mail account on Thunderbird, but I keep getting authentication errors.

Account:
info@baktradingtn.com

Domain: baktradingtn.com

Settings used:

  • IMAP: imap.zoho.com, Port 993, SSL/TLS, Normal Password

  • SMTP: smtp.zoho.com, Port 465, SSL/TLS, Normal Password

  • Username: full email address

What I tried already:

  • Enabled IMAP access in Zoho Admin and applied correct policy.

  • Tested with both my normal Zoho password and an App Password (generated from Zoho Security).

  • Deleted old saved credentials in Thunderbird and re-entered.

  • Confirmed configuration is correct (Thunderbird detects servers).

Problem:
Zoho’s servers reject the login with “Authentication Error” in Thunderbird, even when using the correct App Password.

Could you please check if my account requires a different method (e.g. region-specific settings, special App Password format, or domain configuration)?

Thank you in advance for your help.

Best regards,
khaled Ben Ali