What does rebuild do in mac mail

In macOS Mail, the "Rebuild" option is used to rebuild the Mail database, which can help resolve various issues and errors that may occur with your email account or mailbox.

When you rebuild the Mail database, Mail creates a new database file and copies all your email messages, accounts, and settings from the old database to the new one. This process can help resolve issues such as:

1. Corrupted database: If the Mail database becomes corrupted, rebuilding it can help restore your email data and fix errors.
2. Missing or duplicate emails: Rebuilding the database can help resolve issues with missing or duplicate emails.
3. Account issues: Rebuilding the database can help resolve issues with your email account, such as login problems or failed syncs.
4. Performance issues: Rebuilding the database can help improve Mail's performance and speed.

To rebuild the Mail database on a Mac:

1. Open Mail.
2. Go to Mail > Preferences.
3. Click on Accounts.
4. Select the account you want to rebuild from the list.
5. Click on the Advanced tab.
6. Click on the Rebuild button.

Note: Rebuilding the Mail database will delete all your email account settings, including your password, and you'll need to re-enter them after the rebuild process is complete.

Before rebuilding the database, make sure to:

• Back up your email data to an external drive or cloud storage service, in case something goes wrong during the rebuild process.
• Close any other email clients or apps that may be accessing your email account.
• Be prepared to re-enter your email account settings and passwords after the rebuild process is complete.

Remember that rebuilding the Mail database is a last resort and should only be done if you've tried other troubleshooting steps to resolve your issue.