pem vs. ppk files

pem file is used to connect to a Cloud VM (like, Amazon EC2) via SSH.

pem file cannot be used to connect on Windows through puTTY - A SSH client

So, .pem file must be converted to .ppk

How to convert pem to ppk ?

Install PuTTY and open PuTTYGen.

Open menu "Conversions" and click Import key

Load .pem file that you downloaded and click Save Private key

Note : Leave passphrase blank.

Save the ppk file at the location which is configured in PuTTY for saving keys.