Use the sidebar of the Storage pane to sort through items by category, see how much space is used, and quickly find documents, apps, books, movies, backups, and other files. Then delete what you no longer need.
Note: The categories you see vary, depending on the apps and files on your Mac.
Choose Apple menu > About This Mac, click Storage, then click Manage.
Click a category in the sidebar:
Applications, Music, TV, Messages, and Books: These categories list files individually. To delete an item, select the file, then click Delete.
Note: If you delete an item that you got from the iTunes Store, the App Store, or Apple Books using your Apple ID, the item is still in iCloud, and you can download it again.
Documents: See all the documents on your Mac. You can quickly view large files or downloads by clicking the corresponding button, and sort files by clicking Name, Kind, Last Accessed, or Size near the top of the window. You can also click File Browser to view the contents and amount of storage used by various folders in your file system.
Note: Some folders and files that are already represented by categories in the sidebar—other than Documents—are dimmed.
To delete a file, select it, then click Delete; click Show in Finder to view the file in the Finder.
iCloud Drive, Photos, Music Creation, and Mail: These categories provide general recommendations for optimizing storage. To accept the recommendation, click the button.
iOS files: See iOS backup and firmware files listed individually. To delete an item, select the file, then click Delete.
Trash: Click Empty Trash to erase all the items in the Trash.
Is it possible to uninstall and reinstall the Mail app without reinstalling the entire OS?
Sorry, but no.
Locate the app and remove the Adobe Reader application to the Trash. After that, you can empty the app within the Trash. Step 2In order to uninstall Adobe Acrobat Reader on Mac completely, you have to remove the caches, logs and more other leftovers that still remain on your Mac. /Library/Application Support/Adobe /Library/Caches/Adobe. Apple recently announced that iPhone and iPad users can finally delete pre-installed Apple apps.That means you can get rid of superfluous apps you never use, such as Compass and Tips, perhaps. How to Delete an App on Mac from Launchpad. The first way we want to recommend to you is using.
Have you tried either rebuilding the particular email account that is having the issue or rebuilding the entire message database?
To rebuild a single or multiple Apple Mail mailboxes:
To rebuild the Mail app message database:
~/Library/Mail/V3/MailData