Convert .pem to .ppk file format Using Putty(Windows)
 
To convert the .pem file .ppk follow below points
 
    1. First you need to download Putty from here.
    2. Then run puttygen to convert .PEM file to .PPK file.
    3. Start puttygen and select “Load”
    4. Select your .PEM file.
    5. Putty will convert the .PEM format to .PPK format.
    6. Select “Save Private Key” A passphrase is not required but can be used if additional security is required.