A.5.2 Where does PuTTY store its data?

On Windows, PuTTY stores most of its data (saved sessions, SSH host keys) in the Registry. The precise location is

HKEY_CURRENT_USER\Software\SimonTatham\PuTTY

and within that area, saved sessions are stored under Sessions while host keys are stored under SshHostKeys.

PuTTY also requires a random number seed file, to improve the unpredictability of randomly chosen data needed as part of the SSH cryptography. This is stored by default in a file called PUTTY.RND; this is stored by default in the ‘Application Data’ directory, or failing that, one of a number of fallback locations. If you want to change the location of the random number seed file, you can put your chosen pathname in the Registry, at

HKEY_CURRENT_USER\Software\SimonTatham\PuTTY\RandSeedFile

You can ask PuTTY to delete all this data; see question A.8.2.

On Unix, PuTTY stores all of this data in a directory ~/.putty by default.