Pageant does not load SSH-2 key generated with GitBash

The Pageant can load keys in the PuTTY format (.ppk) only.

If you attempt to load a key in a different format, still recognized by PuTTY tools, you get the mentioned error message:

Couldn't load this key (OpenSSH-SSH-2 private key)

You need to use the PuTTYgen to convert the key from the OpenSSH format to the PuTTY format. If the Pageant recognized the file format, the PuTTYgen can convert it.

  • Run PuTTYgen;
  • Press Load to load the private key in OpenSSH format;
  • Press Save private key to save the private key in .ppk format;
  • Now you can load the private key in .ppk format to Pageant.

Or even easier, use the PuTTYgen to create the a key directly in the PuTTY format, instead of using the ssh-keygen.

See the PuTTY wishlist for reasons it has its own key format:

Note that I believe there's no standard for SSH-2 private key file format.