HELP PLEASE - Avast - Concurrent Connection Limit Exceeded (Mailbird)

I have friend who is using Avast and Mailbird.
(currently free version, but may upgrade)

They keep getting concurrent connection errors when sending emails

Concurrent connection limit in Avast Exceeded

I have searched for forum, and in particular this thread - Related to https://forum.avast.com/index.php?topic=181383.0

Which references a file here → C:\ProgramData\AVAST Software\Avast\EmailShield.ini
to then enter following details:

[EmailScanner]
MaxConnections=75

BUT I cannot find this file.
I did find an Avast.ini - but this does not contain and EmailScanner section or any MaxConnections settings.
I also checked all through the application settings, but cannot find anywhere to increase max connections.

using Windows 10 and Avast 18.2.2328

Queries:
a) Any ideas how to stop this intermittent and annoying issue.
b) What is default max connections set in Avast ?
c) What should I set it to ?

In advance - Many thanks

The EmailShield.ini file ‘should’ be in the location stated in my post of that topic along with other avast .ini files. See Attached image, though this one is from my WinXP system I’m on at the moment, it should be present in the C:\ProgramData\AVAST Software\Avast\ location

There is a possibility that it may not be there if you haven’t changed anything in the Mail Shield settings, try making some changes in the Mail Shield settings and see if that generates the file.

Your Mailbird is eating all of the connections, so the Mail Shield hasn’t got any to scan the content. I don’t know if there is a setting in mailbird to throttle the number of concurrent connections.

The default setting for the max connections for the Mail Shield is 50 (hence the max connection error), but you can change that in the Mail Shield UI only in the .ini file.

In the topic it is suggested you set it to 75, but you could find that if you assign a higher number that mailbird will just keep eating those also. It is a case of testing to find a balance. As mentioned you can also set it to 0, disable the limit. This however is loot unless you can find and edit the EmailShield.ini file.