At the day of your exam you need to visit the link provided by the Proctor.
The proctor will unlock the exam by entering his/her password and then you will need to enter the ICSI exam voucher code and press Continue. (Exam Vouchers)
The below instructions apply ONLY to practical hands-on exams (CPT | CWPT | CDFE)
Then you will need to go to the following url http://icsi.learnondemand.net and login using your existing credentials to start the new exam lab assigned to you.
Then all you have to do is to launch the Exam Lab and start answering the questions.