Windows 10 OpenSSH: Migrating from PuTTy: Importing existing keys

This article is the third of a series I’ve written about migrating from using PuTTy on Windows to using the native OpenSSH client now available on Windows 10: you can read the rest of the articles via:

1. Installation
2. Storing keys using the SSH Agent
3. Importing existing keys < You are here
4. Creating a new public/private key pair
5. Other useful OpenSSH commands
6. Configuring Windows Git

If you’ve been using SSH for a while, you’ve probably got a variety of private keys in either PuTTy’s own “PPK” format or OpenSSH format. Windows OpenSSH only has support for OpenSSH keys (go figure from the name! 😉 ) and so any PuTTY keys will need converting first.

Converting PuTTy PPK Private Keys to OpenSSH format

1. Open PuTTyGen
2. Select “Load an existing private key file” and select your .ppk private key
3. Select from the menu “Conversions->Export OpenSSH key”
4. Save the file.
5. Repeat the previous three steps as necessary for all .ppk files

Adding OpenSSH private keys

In a normal PowerShell window (i.e. not as administrator), just run:
ssh-add C:\Users\userName\.ssh\private_key
Of course, changing the path of the key appropriately!

Windows appears to accept standard private keys and .pem private keys