Email will not connect: antivirus mail shields (AVG, Avast, Norton)

If Booked Solid cannot connect your email, or it worked yesterday and stopped today, and you see something like "Could not reach that mail server. Check the server name and port", the most common cause is not your password and not your settings. It is the mail shield inside your antivirus.

Why this happens

AVG, Avast and Norton all ship a component that inspects your email as it arrives. To read mail that is encrypted in transit, that component has to sit in the middle of the secure connection between your computer and your mail provider. Booked Solid opens exactly that kind of secure connection, sees a stranger in the middle of it, and refuses to continue. Your antivirus is doing what it was designed to do; it simply breaks a connection our app is right to protect.

The important part: exclusions do not fix this

Almost everyone tries this first, and it is a dead end. Exclusion lists work on files and folders. The mail shield is not scanning a file, it is intercepting a network connection, so no path you add to an exclusion list will ever apply to it. One of our customers spent days adding every exclusion he could find before discovering this. Skip that step.

The fix

Turn off the mail shield specifically. This is not turning off your antivirus, and everything else it protects keeps running.

AVG

1. Open AVG and go to Menu > Settings.
2. Choose Basic Protection (older versions call it Components).
3. Find Email Shield and switch it off.
4. Go back to Booked Solid and connect your email again.

Avast

1. Open Avast and go to Menu > Settings > Protection > Core Shields.
2. Switch off Mail Shield.
3. Connect your email again.

Norton

1. Open Norton and go to Settings > Antispam (some versions: Settings > Firewall > Email).
2. Turn off Email Antivirus Scan or Email Protection.
3. Connect your email again.

How to be sure this is your problem

Switch the mail shield off, try the connection once, and watch what happens. If it connects immediately, you have your answer. If it still fails, turn the shield back on, because the cause is something else and we should look at it together.

Is it safe to leave the mail shield off?

For most performers, yes, and here is the honest reasoning. Your mail provider already scans everything for viruses before it ever reaches you, your antivirus still scans any attachment the moment you open or save it, and every other shield stays on. The mail shield is a second layer on top of protection you already have, and it is the layer breaking your booking department.

If you would rather keep it on, your company requires it, or you are on a managed work computer, reply to this article's ticket or open one at our help desk and we will work through your specific product with you. Do not sit stuck on it.

Still stuck?

Open a ticket and tell us which antivirus you use and what the exact error says. We usually answer within minutes.

Thanks to Harry Maurer, who found this the hard way and wrote it up for everyone else.