Printer Scan to Email Not Sending – Quick Fixes That Work

1. SMTP Server Settings – The Real Culprit 90% of the Time

I've seen this a hundred times. You set up scan to email last year, everything worked fine. Then one day it just stops sending. The printer says "email sent" but the recipient never gets it. Or you get a connection timeout error.

The issue is almost always the SMTP server settings. Here's why: email providers change their SMTP requirements all the time. Google, Microsoft, Yahoo – they all keep tightening security. Your printer still has the old settings from 2021. That's your problem.

What to Check First

Log into your printer's web interface. Usually it's the printer's IP address typed into a browser.
Go to the email or scan settings page.
Look for SMTP server address, port, and authentication.

Here are the current working SMTP settings for the big providers:

Provider	SMTP Server	Port	Security	Authentication
Gmail / Google Workspace	smtp.gmail.com	587	STARTTLS	Yes – use full email address and app password
Outlook / Office 365	smtp.office365.com	587	STARTTLS	Yes – use full email address and password or app password
Yahoo Mail	smtp.mail.yahoo.com	587	STARTTLS	Yes
Custom / Company Exchange	Ask your IT team	587 or 25	STARTTLS or None	Depends on setup

Port 465 is for SSL only. Most printers don't support it well. Stick with port 587 and STARTTLS. If your printer is old (like a Brother MFC from 2015), it might not support STARTTLS. In that case, you're stuck using port 25 with no encryption – but that's a security risk and many ISPs block port 25 now.

The App Password Trick

Gmail and Outlook now block "less secure apps" – and your printer counts as one. You need an app password. Here's how:

Gmail: Go to your Google Account > Security > App passwords. Generate one for "Mail" and your printer model. Use that password in the printer, not your regular Gmail password.
Outlook: Same idea – enable multi-factor auth, then create an app password from the security page.

If you don't do this, the printer will keep failing with an "authentication failed" error. Or worse – it'll say sent but the email never leaves the queue.

2. Printer's Date and Time is Wrong

This one sounds stupid but I've lost count of how many times it's been the fix. Printers are dumb about time. If the battery inside dies (yes, they have a tiny battery for the clock), the date resets to 1970 or 2000. SMTP servers see that and reject the connection.

Check the date and time on the printer's control panel. If it's wrong, fix it. Better yet – enable NTP (Network Time Protocol) if your printer supports it. That way it syncs automatically with the internet.

Quick test: Set the date manually to today. Try sending a scan again. Works? Then NTP is your permanent fix.

3. Firewall or Network Blocking SMTP Traffic

Your printer is sending email through your network. Some corporate networks, or even home routers, block outgoing SMTP traffic on ports 25, 465, and 587. The fix is simple but you need router access.

Find your printer's IP address (usually from the printer's network settings page).
Log into your router.
Look for "Port Forwarding" or "Access Control". Some routers call it "Application Filtering".
Make sure outbound traffic to port 587 (or whatever port you're using) is allowed for the printer's IP.
Also check if there's a firewall rule blocking SMTP. If you see a rule that says "Block SMTP", remove the printer from that rule.

If you're on a corporate network, talk to IT. They might have a dedicated SMTP relay server you should use instead of Gmail or Outlook directly. Ask them for the SMTP server address, port, and whether authentication is needed.

Quick-Reference Summary Table

Cause	What to Check	Fix
Wrong SMTP settings	Server, port, security type	Use smtp.gmail.com:587 with STARTTLS and app password
Wrong date/time	Printer's clock	Set manually or enable NTP
Firewall blocking SMTP	Router or network firewall	Allow outbound traffic on port 587 to the printer's IP

That's it. Three things. Start with #1 – it fixes most cases. #2 is a 2-minute check. #3 is for stubborn cases where everything looks right but it still fails. If none of these work, your printer's firmware is probably too old to work with modern email security. In that case, look into a scan-to-folder setup instead. But 90% of the time, one of these fixes gets the job done.