The use of a persistent volume in a system which is designed to provide anonymity and leave no trace is a complicated issue.
Read carefully the warning section.

To start the persistent volume assistant, choose Applications ▸ Tails ▸ Configure persistent volume.

The error message Error, Persistence partition is not unlocked. means that the persistent volume was not enabled from Tails Greeter. So you can not configure it but you can delete it and create a new one.

When run for the first time, or after deleting the persistent volume, the assistant proposes to create a new persistent volume on the USB stick. Refer to our installation instructions for more guidance on creating the persistent volume.

Persistence features

Restart Tails to apply the changes after selecting or unselecting one or several features.
Only features that are listed here can currently be made persistent. Some other features have been asked and accepted, but are waiting to be implemented: browser extensions, wallpaper, RSS feeds, default sound card, mouse and touchpad settings, etc. See the corresponding tickets for more details.
If you unselect a feature that used to be activated, it will be deactivated after restarting Tails but the corresponding files will remain on the persistent volume.

Personal Data

When this feature is activated, you can save your personal files and working documents in the Persistent folder.

To open the Persistent folder, choose Places ▸ Persistent.

GnuPG

When this feature is activated, the OpenPGP keys that you create or import are saved in the persistent volume.

If you manually edit or overwrite the ~/.gnupg/gpg.conf configuration file you may lessen your anonymity, weaken the encryption defaults or render GnuPG unusable.

SSH Client

When this feature is activated, all the files related to the secure-shell client are saved in the persistent volume:

  • The SSH keys that you create or import
  • The public keys of the hosts you connect to
  • The SSH configuration file in ~/.ssh/config
If you manually edit the ~/.ssh/config configuration file, make sure not to overwrite the default configuration from the /etc/ssh/ssh_config file. Otherwise, you may weaken the encryption defaults or render SSH unusable.

Pidgin

When this feature is activated, all the configuration files of the Pidgin Internet messenger are saved in the persistent volume:

  • The configuration of your accounts, buddies and chats.
  • Your OTR encryption keys and keyring.
  • The content of the discussions is not saved unless you configure Pidgin to do so.

All the configuration options are available from the graphical interface. There is no need to manually edit or overwrite the configuration files.

Pidgin fails to load any account if you enable persistence and select the Read-Only check box as a startup option.

Don't use the Read-Only option if you want to use Pidgin. See #8465.

Icedove

When this feature is activated, the configuration and emails stored by the Icedove email client are saved in the persistent volume.

GNOME Keyring

When this feature is activated, the secrets of GNOME Keyring are saved in the persistent volume.

GNOME Keyring is a collection of components in GNOME that store secrets, passwords, keys, certificates and make them available to applications. For more information about GNOME Keyring see the official documentation.

Network Connections

When this feature is activated, the configuration of the network devices and connections is saved in the persistent volume.

To save passwords, for example the passwords of encrypted wireless connections, the GNOME Keyring persistence feature must also be activated.

Browser bookmarks

When this feature is activated, changes to the bookmarks in Tor Browser are saved in the persistent volume. This does not apply to the Unsafe Browser.

Printers

When this feature is activated, the configuration of the printers is saved in the persistent volume.

Bitcoin Client

When this feature is activated, the bitcoin wallet and preferences of the Electrum bitcoin client are saved in the persistent volume.

APT Packages

When this feature is activated, the packages that you install using the Synaptic package manager or the apt-get command are saved in the persistent volume.

If you install additional programs, this feature allows you to download them once and reinstall them during future working sessions, even offline.

To reinstall these packages automatically when restarting Tails, use the Additional software packages persistence feature.

If you activate the APT Packages persistence feature, it is recommended to activate the APT Lists feature as well.

APT Lists

When this feature is activated, the lists of all the software packages available for installation are saved in the persistent volume.

Those so called APT lists correspond to the files downloaded while doing Reload from the Synaptic package manager or issuing the apt-get update command.

The APT lists are needed to install additional programs or explore the list of available software packages. This feature allows you to reuse them during future working sessions, even offline.

Dotfiles

When this feature is activated, all the files in the /live/persistence/TailsData_unlocked/dotfiles folder are linked in the Home folder. Files in subfolders of dotfiles are also linked in the corresponding subfolder of your Home folder.

For example, having the following files in /live/persistence/TailsData_unlocked/dotfiles:

/live/persistence/TailsData_unlocked/dotfiles
├── file_a
├── folder
│   ├── file_b
│   └── subfolder
│       └── file_c
└── emptyfolder

Produces the following result in /home/amnesia:

/home/amnesia
├── file_a → /live/persistence/TailsData_unlocked/dotfiles/file_a
└── folder
    ├── file_b → /live/persistence/TailsData_unlocked/dotfiles/folder/file_b
    └── subfolder
        └── file_c → /live/persistence/TailsData_unlocked/dotfiles/folder/subfolder/file_c

This option is useful if you want to make some specific files persistent, but not the folders they are stored in. A fine example are the so called "dotfiles" (and hence the name of this feature), the hidden configuration files in the root of your home directory, like ~/.gitconfig and ~/.bashrc.

As you can see in the previous example, empty folders are ignored. This feature only links files, and not folders, from the persistent volume into the Home folder.

Additional software packages

This is an experimental feature which does not appear in the assistant.

When this feature is enabled, a list of additional software of your choice is automatically installed at the beginning of every working session. The corresponding software packages are stored in the persistent volume. They are automatically upgraded for security after a network connection is established.

To use this feature you need to enable both the APT Lists and APT Packages features.

If you are offline and your additional software packages don't install, it might be caused by outdated APT Lists. The issue will be fixed next time you connect Tails to Internet with persistence activated.

To choose the list of additional software, start Tails with an administrator password and edit (as an administrator) the file called /live/persistence/TailsData_unlocked/live-additional-software.conf. Each line of this file must contain the name of a Debian package to be installed as an additional software package.

For example, to automatically install the dia software, a diagram editor, and the font-manager software, a font manager, add the following content to live-additional-software.conf:

dia
font-manager

To learn about the many software packages available in Debian, visit http://packages.debian.org/stable/.

Installing additional software is at your own risk. Most additional software requires extra configuration to be able to connect to the network through Tor, and will not work otherwise. Some other software might, for example, modify the firewall and break the security built in Tails. Software not officially included in Tails is not tested for security.