Fetching Ubuntu's OpenPGP keys for verification fails with "not a key ID: skipping"

Question

I have entered this request into the "Terminal" program, per this documentation

gpg --keyserver hkp://keyserver.ubuntu.com --recv-keys "8439 38DF 228D 22F7 B374 2BC0 D94A A3F0 EFE2 1092" "C598 6B4F 1257 FFA8 6632 CBA7 4618 1433 FBB7 5451"

and received the expected responses:

gpg: directory /home/ubuntu/.gnupg' created
gpg: new configuration file `/home/ubuntu/.gnupg/gpg.conf' created
gpg: WARNING: options in `/home/ubuntu/.gnupg/gpg.conf' are not yet active during this run
gpg: keyring `/home/ubuntu/.gnupg/secring.gpg' created
gpg: keyring `/home/ubuntu/.gnupg/pubring.gpg' created

but the response to

gpg: requesting key EFE21092 from hkp server keyserver.ubuntu.com

was:

gpg: "8439 38DF 228D 22F7 B374 2BC0 D94A A3F0 EFE2 1092" not a key ID: skipping
gpg: "C598 6B4F 1257 FFA8 6632 CBA7 4618 1433 FBB7 5451" not a key ID: skipping

The "trustdb" was not created, the "Ubuntu CD Image Automatic Signing Key (2012) " was not imported, the "Ubuntu CD Image Automatic Signing Key " was not imported.

Solution

This seems to be same issue others had with GnuPG on Windows and Mac OS X, reported on Super User in the question "gpg2 not a key id: skipping” when trying to download public keys":

While the command works fine under GnuPG on Linux, it fails in Windows. I've been able to make it work by removing all spaces:

gpg --keyserver hkp://keyserver.ubuntu.com --recv-keys 843938DF228D22F7B3742BC0D94AA3F0EFE21092

C5986B4F1257FFA86632CBA746181433FBB75451

(the quotes are not required any more, either; so I removed them).

If you really want to verify against signatures from Ubuntu, you obviously shouldn't copy/paste this specific command line as is, but remove the space from the original Ubuntu page on your own.

The solution will be the same, and you should get the command running by removing the spaces in the fingerprints (the hexadecimal numbers).