Upvote:5
I had to turn my laptop on during at-gate security check (separate from the main security check) when flying from Europe to USA. Security lost all interest of it as soon as they seen the boot loader prompt, nobody asked to log in. This only happened twice out of over hundreds of those flights, and in those cases every passenger went through this check. No idea what triggered it, and it looks like all US-departing flights were through this check. Looked like occasional thing to me.
Last time I flew from EU (AMS) to USA was in late June 2017, and there were no checks nor restriction.
Upvote:7
I see up to three security checks you'll be going through. If they search your laptop, it will surely be at customs/immigration.
The anti-hijacking guys are looking for one thing: a laptop that's been hollowed out to conceal a knife, gun, dynamite, whatever. Their de-facto test is that the laptop powers up normally, acts like a working device, and doesn't have signs of tampering. You do this right in front of them.
The immigration and customs guys are looking at data about you. They may do this in a separate room where they are equipped for high speed forensic analysis of laptops etc. They may also open your checked bags to look at laptops, hard drives, USB fobs, etc. This is for two reasons: