Why does Apple Mail under Big Sur not work at all?

Chaynes4 wrote:

I've been using Macs since 1985. Big Sur is the first time an operating system has completely destroyed some commonly used feature of the computer system. Apple Mail is completely unusable, won't load... spinning ball. I made a "safe" boot to get the latest Big Sur to install thinking that might help... no. Why, after all these years is Mail the stepchild of this platform when I suspect it may very well be one of the most used applications? I relied on the "Mark As Unread" entity in "Rules", got used to it and , of course, it's in and out. Right now it is no longer an option. Stop making jewelry and start giving us the basic services we need... day to day. Sheeesh!!

Set up a new user and test Mail— it should not be an issue...

submit your Apple Feedback http://www.apple.com/feedback

Download and run Etrecheck. Etrecheck is a diagnostic tool that was developed by one of the most respected users here in the ASC and recommended by Apple Support  to provide a snapshot of the system and help identify the more obvious culprits that can adversely affect a Mac's performance.

IMPORTANT:

Before running Etrecheck assign Full Disk Access to Etrecheck in the Etrecheck's Privacy preference pane so that it can get additional information from the Console and log files for the report:

Also click and read the About info to further permit full disk access.

Copy the report

and use the Additional Text button to include the report in your reply.

Then we can examine the report and see if we can determine what might be causing the problem.

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