Neither the US nor the UK ask for notarized affidavits for visa applications to attend a conference. You go there with your plane ticket, a letter of invitation from the organizers (and/or just the conference registration fee printout), a letter from your employer .. travel insurance for the schengen countries. And of course about six months worth of bank statements, three years of tax returns etc, sigh .. I hate leaving copies of that around in embassies, to be later trashed and dug out by dumpster divers and ID thieves, no doubt.

The argentinian visa clerk had that "indian govt department clerk" type attitude, including, for example, insisting that the handwritten declaration I got sealed by a notary wasnt acceptable, I had to get it typewritten before being endorsed. And then telling me "do what I say or you can apply for six months and not get a visa all". Even when I kept telling the guy it was a conference organized by the argentinian government that I'd been invited to.

This after I'd had to fly to Delhi to apply personally for this. I flew back to MAA, told the conference organizers to sort it out with their colleagues in the Delhi embassy. After which my visa suddenly came through with far less pain, notwithstanding that visa clerk.