"Finally, and somewhat overdue, here is the vReference card updated for vSphere 4.1. At first glance it looks the same, but there was quite a few little additions here and there."
I re-logged into the machine and found that they are not in place still. I surprised and made relogin again, this time they mapped. Finally after applying multiple tests like this, I came to a conclusion that, I have below two problems…
1) Drive mapping is not happening at every attempt 2) Background processing of drive mapping is not working"