Fail to get current version for host "protocol error"

Felipe1 · April 3, 2026, 10:29pm

The system seems to be working normally, but when I updated today, the system couldn’t tell me my current version.

Karl_Wagner · April 4, 2026, 3:53pm

Same here.

Also “updatectl update” now returning: host: x Invalid argument

Paul_Brown · April 4, 2026, 3:54pm

Do an

updatectl vacuum

and try again, see if it helps (it helped me).

ngraham · April 4, 2026, 6:04pm

I believe this is a known systemd bug: updatectl stuck showing "Failed to get current version for 'host': Protocol error" · Issue #41303 · systemd/systemd · GitHub. Looks like it’s gotten fixed today! That fix should make it into KDE Linux as soon as it’s in a tagged release.