After starting Tails and connecting to Tor, <span class="application">Tails Upgrader</span> automatically checks if upgrades are available and then proposes you to upgrade your USB stick. The upgrades are checked for and downloaded through Tor.
<p>If you cannot upgrade at startup (for example, if you have no network connection by then), you can start <span class="application">Tails Upgrader</span> later by opening a terminal and executing the following command:</p>
The automatic upgrade is impossible for technical reasons (not enough memory, not enough free space on the USB stick, and so on). For example, if you get the following error message: