I’m unable to open emails after downloading Mac OS Monterey

If there is AntiVirus software installed - one is paying money for an Non-Existent issue that affects macOS.

The The Built in Security is all that is required to protect the computer.

There are no known Windows-like Viruses in the wild that self replicate and affect macOS, because of the underling UNIX  Foundation and Permission Limitation. 

Should “ Certain & Specific Software “ referenced from above be installed - it will negatively impact macOS. It is suggested, to download directly from a respected ASC Contributor, the application Malwarebytes for Mac. 

It is free or paid for added features. 

Disclaimer: I am not affiliated with nor receive compensation from the Developer.

Run the Application and it should remove the malware / adware. Once done, restart computer and test.

Remove any 3rd party antivirus software you have installed.

See https://discussions.apple.com/thread/253303599?login=true&page=1

This is a common problem but easily rectified