unable to install the backup server using srvbuildres

I am unable to install the backup server with resource file

it gives weiored message which i didnot come across till now.

Open Server Error: 16400.10.0: srv__e3_create_encrypt3_context: Unexpected failure in comn_keypair_create.

Open Server Error: 16400.10.0: srv__e3_handshake: Unexpected failure in srv__init_encrypt3.

Open Server Error: 16400.10.0: srv__handle_password_negotiation: Unexpected failure in srv__e3_handshake.

Open Server Error: 16400.10.0: srv__e3_create_encrypt3_context: Unexpected failure in comn_keypair_create.

Open Server Error: 16400.10.0: srv__e3_handshake: Unexpected failure in srv__init_encrypt3.

Open Server Error: 16400.10.0: srv__handle_password_negotiation: Unexpected failure in srv__e3_handshake.

this is all in the backuplog and it fails saying unable to boot the server and task failed and backup server not started.

i see that the password encryption is not on i got that by running sp_helpserver <backupsever name>

the staus i got when i ran sp_helpserver is "timeouts, no net password encryption, writable , enable login redirection"

Please help me installing my backupserver.

many thanks in advance.