Virus

I have found that Avast Free on my PC is letting emails containing a virus/spam through although Avast mobile is not

You can report a suspicious/malicious sample (File/Website) here: https://www.avast.com/report-malicious-file.php

Can you give more details.

  1. What is your email client, is it webmail or email program (thunderbird, etc.) ?

  2. How do you know this, e.g. what did detect it ?

  3. What was detected ?

  4. If you are using a regular PC based email client and the regular Mail Shield, then I see nothing in the shield setting about Spam Detection.

  5. If your email program is MS Outlook, that does have an anti-spam function, but you must be using the avast plugin for MS Outlook.

Hopefully you can see we need more information.