SFTP - Invalid Private Key Error

Hi Community,

I am facing issue while using the SSH Key Pair authentication for SFTP. So when I am trying using Basic Credentials, I am able to establish the connection with Remote Directory and able to Send and Receive File. But for same username when I am trying through SSH Key Pair authentication I am getting error as "invalid privatekey: [B@41050c98". I have generated the Key Pair through Puttygen software, and the Remote directory Team has configured the Public Key on there end. 

Please if anyone have any idea regarding this help me

Thanks,

Prathamesh