9.3.1 Making Pageant automatically load keys on startup
Pageant can automatically load one or more private keys when it starts up, if you provide them on the Pageant command line. Your command line might then look like:
C:\PuTTY\pageant.exe d:\main.ppk d:\secondary.ppk
If the keys are stored encrypted, Pageant will request the passphrases on startup.
If Pageant is already running, this syntax loads keys into the existing Pageant.