Scan to email stopped working with Gmail — why, and how to fix it
If your office printer's scan-to-email stopped working and the error mentions authentication, username or password, your printer almost certainly hasn't broken — Google changed the rules.
What changed
Google progressively removed support for what it calls “less secure apps” — plain username-and-password
SMTP sign-in — for Google Workspace and Gmail accounts. Printers were the classic example: an MFP signs in
to smtp.gmail.com with an account name and password, which is exactly the pattern Google
withdrew. Microsoft did the same thing to Exchange Online. The result was thousands of offices whose scan
button stopped working overnight, with no change on the printer at all.
Why the usual workarounds disappoint
- App passwords. They still work in some configurations, but they require 2-step verification on the account, they are invisible to your normal password policy, and Google has narrowed their availability more than once. Anything built on them may break again.
- A dedicated Gmail account for the printer. Same fragility, plus a shared credential sitting in a device menu that any visitor can read off the panel.
- An internal SMTP relay. This genuinely works, and if you already run one it's a fine answer. But standing up and maintaining a relay — DNS, TLS certificates, IP reputation, spam filtering, patching — is a real ongoing job for the sake of a scan button.
- Scan to folder / USB instead. Works, but it moves the problem to whoever has to fetch the file.
The straightforward fix
Point the printer at an SMTP endpoint built for printers rather than for people. Scanhive gives each device its own short username and password, accepts the old SMTP dialects that MFP firmware speaks, and then delivers the scan onward from a properly authenticated, verified sending domain — so the mail arrives in Gmail and Microsoft 365 mailboxes normally.
Nothing changes about your mailboxes. You don't move email providers, and you don't give the printer a credential to a real person's account.
What the settings look like
| SMTP server | smtp.scanhive.net |
| Port | 587 (or 25 on older devices) |
| Encryption | STARTTLS if offered — plain works for older firmware |
| Authentication | SMTP AUTH (LOGIN or PLAIN) |
| Verify server certificate | Off — see the note below |
| Username | from your dashboard, e.g. prn_ab12cd34 |
| Password | shown once when you add the printer (rotate any time) |
Brand-specific walkthroughs: Brother, Canon, HP, Xerox, Ricoh, Kyocera.