I was interviewed at US embassy New Delhi on sep 13,2012 for immigrant visa. At the end of interview the officer told me that visa is approved and I will get it by courier in couple of days. But its nearly a week, I have not received anything yet, even the vfs tracking is not working for me. Can they refuse it after approval
Thanks
Rajveer

I am sure they can refuse if they wish, but I doubt that is the problem. Tracking doesn't always show correctly or show anything at all in my experience, and 6 days isn't out of range for any delivery, and 'a couple of days' could just be someone's way of saying 'not too many days.' Try to find out the tracking details in person (I am in the US and don't know vfs, but are there physical buildings near you to ask?) or by phone. If there is a tracking number at all, that should mean it's been sent.

I was interviewed at US embassy New Delhi on sep 13,2012 for immigrant visa. At the end of interview the officer told me that visa is approved and I will get it by courier in couple of days. But its nearly a week, I tracked it this morning, they said my passport is still with US embassy New Delhi under processing.
Can anyone tell me what sort of processing is going on there?
Thanks
Rajveer

(You should have put this as an Answer under your first question.)

I still think it's just routine and you have nothing to worry about once approved. Call the embassy. Processing can mean mail processing, but I don't know what you are looking at - the visa processing or the mail tracking. Tracking isn't always current. Even for us in the US, where the post office is highly organized and usually accurate.

I actually called VFS this morning, they said they have not received my passport from visa section yet. Vfs is the courier service for us embassy new delhi. They deliver passports next day after receiving it from visa section. In most cases the passports are handed over to vfs on the day of interview or next day. It means my passport is still under processing inside US Embassy. I am 100% sure that the officer said "your visa is approved, you will get your passport in 4 to 5 days". What I am worried about is can they change decision after? If not then why are they taking so long just to place visa inside passport?The wait is killing me.
Please give your views about this
Thanks
Rajveer

I actually called VFS this morning, they said they have not received my passport from visa section yet. Vfs is the courier service for us embassy new delhi. They deliver passports next day after receiving it from visa section. In most cases the passports are handed over to vfs on the day of interview or next day. It means my passport is still under processing inside US Embassy. I am 100% sure that the officer said "your visa is approved, you will get your passport in 4 to 5 days". What I am worried about is can they change decision after? If not then why are they taking so long just to place visa inside passport?The wait is killing me.
Please give your views about this
Thanks
Rajveer

Of course an embassy can change their mind if new information is received, but mistakes do happen and are most likely. It sounds like you are worrying about something that is probably a clerical error, and a call to the embassy will clear it up. Paperwork can fall behind counters and under desks and in someone else's envelope.