THUNDERBIRD NOT RECEIVING EMAILS
This could be because of security measures by windows or any other security provider you use. In case you use Windows security, follow the instructions mentioned here to fix Thunderbird not receiving emails. Open Settings and click on Update & Security, click on windows security next and navigate Virus & Threat protection. You will find manage settings option right under it, click on it then on Add or remove exclusions, and finally click on Add an exclusion to select Thunderbird.
Thunderbird Email Not Responding
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