Yesterday Windows Update offered the Windows 10 1511 update. Immediately after downloading was complete, it showed a message that the update failed, along with a Retry button. Pressing the Retry button simply checked for updates again, and told me that no updates are available. Since then the update is never offered again.
What can I do to get Windows Update to offer the update again?
Note: I forgot to remove an SD card from the computer before starting the update. I guess this may have caused the problem, as some websites mention that it should be removed.