Win 8.1 Update failure, error code 80240055

Question

We have a Lenovo laptop about 2 years old that recently failed. We sent it in for "depot repair". It just came back with a new motherboard and reset to when it left the factory. The OS is Win 8.1.  Windows Update was set to update automatically so we let it run overnight, plugged in to mains power. This morning the system shows a long list of updates (as expected) but every one failed to install. I checked a number of the failures and each shows error code 80240055.

So I have several questions -

1. What is error code 80240055 (and why does Microsoft assign error codes and then not make it known what they mean; searching yields no list of error codes and what to do when you get them)
2. after all the failures, don't the downloads at least stay on the system? I reset Win Update to let me manually install updates, but it seems I have to rerun "Checking for Updates" for hours to get the list again 
3. when you know you are going to have a lot of updates, is there anyway to get less than all at once? It would be wonderful if one could ask for, say, 10 at a time, max.

Checking Windows Update History, the most recent cumulative update installed successfully was KB3000850 on 11/21/2014.

So then ... I downloaded and ran the Windows Update Troubleshooter. It indicated that it fixed a couple of things.

I then went to the first update that had failed to install (KB3153704) and tried to install it manually to see if that would work. I downloaded it, saved it, and the double clicked on it. That started the Windows Update Standalone Installer which has subsequently been "searching for updates on this computer" for a very long time. It would be hard to articulate how very frustrating this is.

Answer 1

So, in the end, I was able to answer some of my own questions. The underlying problem, whatever it was, was resolved by the Windows Update Troubleshooter. 

With respect to the time it takes / would have taken / to test whether in fact the problem was solved, I found it helps greatly to go to Windows Update Change Settings and Choose - How Windows Can Install Updates, and select "Check for updates but let me choose whether to download and install them". This ensures that at you are not stuck waiting for downloads, so will shorten the time it takes to check whether the problem is solved. It has the additional benefit that Windows Updates retains the list of updates proposed. It seems when you are set to update automatically and something goes wrong the list of updates is lost and you have to check for them all over again.