Error_logging_mca21

Trying to Logging into MCA 21 system for Uploading of Necessary E Forms for LLP, But Failed to do so for past 7 days. I am using Original Windows 8.1 pro version. The error shown to me is "It is necessary to select Certificate Before Logging in". But my problem is that no window is popping from the MCA site which would allow to select the certificate necessary for Logging in.

If someone is having solution to this problem, kindly please reply.