How to back up manually full mail mac 10.11

To back up your full Mail database manually on a Mac running OS X 10.11 (El Capitan), you can follow these steps:

Method 1: Using the Terminal

Open the Terminal app on your Mac. You can find it in the Applications/Utilities folder, or use Spotlight to search for it.
Type the following command and press Enter:
```
cd ~/Library/Mail/V2/MailData
```
This will take you to the directory where your Mail database is stored.
Type the following command to create a backup of your Mail database:
```
cp -R MailData ~/Desktop/MailBackup
```
This will create a copy of your Mail database on your desktop.
To verify that the backup was successful, you can check the size of the backup folder on your desktop. It should be similar to the size of your original Mail database.

Method 2: Using the Finder

Open the Finder on your Mac.
Navigate to the following directory:
```
~/Library/Mail/V2/MailData
```
You can do this by clicking on the "Go" menu in the Finder menu bar, selecting "Go to Folder", and typing in the path.
Select all the files and folders in the MailData directory by pressing Command+A.
Right-click (or Control-click) on the selected files and folders, and select "Duplicate" from the context menu.
Name the duplicated folder something like "MailBackup" and move it to your desktop or another location of your choice.
To verify that the backup was successful, you can check the size of the backup folder. It should be similar to the size of your original Mail database.

Important notes:

When you back up your Mail database manually, you are creating a copy of your email data, including messages, accounts, and settings. This backup will not include any attachments or large files that are stored on your email server.
If you have a large number of emails or a large Mail database, the backup process may take some time to complete.
It's a good idea to back up your Mail database regularly to ensure that you have a recent copy of your email data in case something goes wrong with your email account or your Mac.