I get the email headings, but the body does not show.

Start with this...

Safe Boot, (holding Shift key down at startup), does the problem occur in Safe Mode? Could take 10 minutes.

Safe mode attempts to repair Disks & clears lots of caches & loads safe Drivers, & prevents loading of 3rd party extensions, so if Safe Mode works try again in regular boot.

Disable or remove your 3rd party anti-virus software.

Great news, take care my friend! :)