PuTTY prompts for a username when starting an SSH session, which slows down repetitive connections and makes it easier to authenticate as the wrong account. Saving a default username in a session profile streamlines logins to the same server or role account.
PuTTY stores connection options as a session profile, including the Auto-login username field under Connection → Data. When the session opens, PuTTY sends that username during the SSH authentication handshake before continuing with password, key-based, or keyboard-interactive prompts.
The auto-login username is not a credential and does not store a password. The setting applies per saved session unless saved as Default Settings, and an incorrect username can cause repeated authentication failures that may trigger lockouts or IP bans on hardened servers.
Skip when configuring a new session from scratch.
Auto-login username stores only the username and does not save a password.
Wrong usernames can trigger authentication failures and may trip account lockouts or IP bans on hardened SSH servers.
Saving as Default Settings applies the username to new sessions created later.
Saving to an existing session name overwrites its previous settings.