Authentication error when trying to set up Zoho account

Problem

I’m trying to set up a Mailspring account for my Zoho email account using IMAP/SMTP. However, Mailspring keeps throwing an authentication error:

Authentication Error - Check your username and password. (IMAP)

With the following logs:

----------IMAP----------
connect <mailcore::IMAPSession:0x16db1f410>
* OK svwall.zoho.com IMAP4 Server (Zoho Mail IMAP4rev1 Server version 1.0)
ssl connect imap.zoho.com 993 2
1 CAPABILITY
* CAPABILITY IMAP4rev1 UNSELECT CHILDREN XLIST NAMESPACE IDLE MOVE ID AUTH=PLAIN SASL-IR UIDPLUS ESEARCH LIST-EXTENDED LIST-STATUS WITHIN LITERAL- ACL CONDSTORE
1 OK CAPABILITY completed
connect ok
login
2 LOGIN "XXXXX@relic-trader.com" "*********"
2 NO [AUTHENTICATIONFAILED] Invalid credentials(Failure)

Context

I’ve verified that my credentials are correct. I have no issues logging directly into Zoho with the credentials I’m entering into Mailspring. No, I don’t have 2FA enabled on Zoho. Yes, I’ve got all SPF, MX, etc. records set up and verified in my DNS panel for my custom domain (relic-trader.com).

Email Provider

Zoho (via IMAP/SMTP)

Setup

  • OS and Version: macOS Sequoia 15.3.1
  • Mailspring Version: 1.15.1