Why is my Mail app not working on Macbook Air?

With Mail 100 % Closed

How many times has the computer been restarted sine the Sonoma 14.6.1 was installed

Sometimes restarting 2 - 3 times is suggested

Still not relief ?

Hold the SHIFT Key and then attempt to launch Mail in Safe Launch mode

Still not relief ?

Restart in Safe Mode. This will perform a Disk Repair, clear cache files and only load Apple Software, extensions and fonts.

The boot up will be slow and can take some time - Normal.

Safe Mode will also eliminate Third Party Software, extensions and drivers from loading.

It will only load the Minimum amount of Core Apple Processes to allow the the computer to function at a reduced Level of Performance 

Does the issue present in this mode ?

There could be something in the main User Account playing up.

To further isolate this - Set up users, guests, and groups on Mac.

Then log out of the Main User account and log into the dummy account and test again if the issue persists.

If the issue is present in the dummy account - then, this appears to be a System Wide issue on the computer.

Download the Application Etrecheck  ( External Link ) directly from the Developer.

The Application is Not a " Silver Bullet "  and is  only a tool to examine the Hardware / Software used on this computer 

This is a Diagnostic Tool that makes no changes to the computer Hardware / Software used on this computer 

The application is free or paid from added features. 

The Report will Not Reveal Any Personal Information. 

Post back the Full Report - copy and paste - >>>> using the Additional Text Icon ( 3rd Icon to last ) <<<<

Thank you.

That narrows down where the issue is >> Your Main User Account <<

Incase this was missed earlier and that can happen

Here it is again

Download the Application Etrecheck  ( External Link ) directly from the Developer.

The Application is Not a " Silver Bullet "  and is  only a tool to examine the Hardware / Software used on this computer 

This is a Diagnostic Tool that makes no changes to the computer Hardware / Software used on this computer 

The application is free or paid from added features. 

The Report will Not Reveal Any Personal Information. 

Post back the Full Report - copy and paste - >>>> using the Additional Text Icon ( 3rd Icon to last ) <<<<

Are we to believe .

ALL the outlined Trouble Shooting Steps, in original rely to your question have been or have not been tried ?

Please clarify before we move forwards with this issue