How to uninstall PuTTY on Windows

PuTTY keeps almost nothing on disk. Saved sessions, host keys and settings all live in the registry under your user account, not in a data folder, so a plain uninstall from Settings does not remove them by itself. This guide covers PuTTY installed machine-wide from the PuTTY.PuTTY winget package.

Quit PuTTY first

Close every open PuTTY window, and Pageant (the SSH key agent) if you have it running from the tray. Check Task Manager (Ctrl+Shift+Esc) for putty.exe or pageant.exe before you uninstall.

Remove the app with its own uninstaller

Go to Settings › Apps › Installed apps, find PuTTY, and choose Uninstall, or run:

winget uninstall --id PuTTY.PuTTY

Back up your saved sessions first

If you saved any sessions in PuTTY (Session name, then Save), they and any host keys you accepted live in the registry, not in a file. Open regedit, go to HKEY_CURRENT_USER\Software\SimonTatham\PuTTY, and export that key (File › Export) before you uninstall if you want to keep them.

Where the data lives

Location	What it holds	What to do
`HKCU\Software\SimonTatham\PuTTY\Sessions`	Your saved sessions, one subkey per session name	Export this key first if you saved any sessions; the uninstaller does not touch it
`HKCU\Software\SimonTatham\PuTTY\SshHostKeys`	Host keys you accepted, so PuTTY does not warn you again	Export with the key above if you want the same trusted hosts after reinstalling
`HKLM\SOFTWARE\SimonTatham\PuTTY`	Machine-wide settings PuTTY itself wrote	Removed by the uninstaller

Check the result

Run these read-only commands after the uninstall finishes:

Get-Process putty, pageant -ErrorAction SilentlyContinue
winget list --id PuTTY.PuTTY
Test-Path "$env:ProgramFiles\PuTTY"
Get-Item "HKCU:\Software\SimonTatham\PuTTY" -ErrorAction SilentlyContinue

No output from Get-Process only means this query observed no matching process; a suppressed error leaves the running state unknown.
A completed winget list query with no match means the package record is gone; a matching row means the uninstall did not finish.
Test-Path returning False means the program folder is gone; True means files remain there.
Get-Item on the registry key prints something only if you saved a session or accepted a host key at some point; it is never touched by uninstalling the app, so remove it yourself once you have backed it up, if you want a clean start.

If you installed it with winget

winget uninstall runs the same MSI uninstaller Settings › Apps uses and removes the same program files and the machine-wide registry key; it never touches your per-user sessions or host keys.

What Mole lists

For PuTTY installed machine-wide from winget, the uninstall review lists nothing: the MSI uninstaller removes the program folder, the Start Menu shortcuts and the machine-wide registry key by itself, so there is nothing left for Mole to offer. Mole also does not show the program folder as a row on its own for this app, because the installer's registry entry does not record an install location; check Program Files\PuTTY yourself if you want to confirm it is gone. Your saved sessions and host keys, kept per-user, are not part of this list either way.

What this test covered

Tested with PuTTY 0.85 installed through winget from the arm64 MSI package, machine scope. No sessions were saved during the test, so the saved-sessions and host-keys registry keys were not exercised.