How to access Zoho Mail in Thunderbird

Setting up my Zoho Mail account in Thunderbird and it will not connect, wrong password despite the password being correct.

What does Zoho need that Thunderbird's setup misses?

The same two Zoho particulars that trip every mail client, covered for Outlook and Apple Mail elsewhere on this forum, apply to Thunderbird and the wrong password message is usually Zoho's refusal in disguise rather than an actual password problem:

1

Enable IMAP in Zoho first, since it is off by default: in Zoho Mail's web settings under Mail Accounts, select the account and switch IMAP Access on. Without this, every client fails with credential style errors regardless of the password being right, the wrong password message being Zoho declining the connection because IMAP is not enabled, the single most common cause.

2

Generate an app password if two factor is on: at Zoho Accounts, Security, App Passwords, create one named Thunderbird and use it instead of your normal password in Thunderbird, since a two factor protected Zoho account rejects the normal password from mail clients.

3

Add the account in Thunderbird with the right servers: incoming imap.zoho.com port 993 SSL, outgoing smtp.zoho.com port 465 SSL, username the full Zoho address and password the app password if you made one. Thunderbird's autoconfig may find these, but set them manually if it stumbles.

4

Use the regional servers for a data center hosted account: an account on Zoho's European or Indian data centers needs imappro.zoho.eu or imappro.zoho.in and the matching smtp hosts, with timeouts rather than password errors being the signature of using the wrong regional host, the region visible in your Zoho settings.

Once connected, Thunderbird treats Zoho as ordinary IMAP with folders syncing both ways and the same account can pair with Thunderbird's calendar and contacts through the appropriate add-ons if you want the full suite in one place. The IMAP off by default trap is genuinely the answer for the vast majority of Zoho connection failures, so if the wrong password persists with a correct password, check that setting before anything else.

IMAP was off exactly as you predicted, the wrong password was Zoho refusing because of it. Enabled IMAP, made an app password since I have two factor and Thunderbird connected on the standard servers first try. The check that setting before anything else advice was spot on.