No Valid OpenPGP data found error while adding gpg key

i’m running stretch lite and using the raspberry pi 2 b.

do i need to be running Jessie?

No, stretch works the same. Perhaps there is an issue with Any ideas @jodal?

Looks like I was wrong, it seems that usage of apt-key in stretch has changed (deprecated?). I think you might be able to use the command as is if you first install gnupg as suggest at Alternatively there are some workarounds at and

I don’t remember running into this problem on my test of Stretch Raspbian Lite a few weeks ago but perhaps I installed gnupg first.