Windows 8.1 Update Error Code: 0x80240031

Windows update reports that there are no important updates.

However the windows update from control panel had two optional updates - one on Win 8 Pro and the other on bing bar.

Will try updating those now.

Meanwhile, tried a couple of reboots - still failed just about at 50% - and it is very slow to download!

fingers crossed now on the optional updates..

Finally - a few more attempts through the night - it worked!

hooray!! now 8.1!!

I am having Sony Vaio E Series laptop with Windows 8 pre-loaded and twice while attempting to upgrade to 8.1 I came across error 0x80240031 after about 50% of download. I also attempted to update Windows 8 after the 1st attempt but I was told that my windows 8 version is updated. Now I am attempting to download it for the 3rd time. Somebody please help.

Different protocols have different level of error detection/correction. I know for sure that in my case FTP of large files does not give right checksum if done by wire, but OK if done by wifi. I have checked it multiple times on four(!) different computers with the same result.

It's not hardware folks.  Maybe 1 in a million.  Microsoft should be ashamed of themselves.  I finally got 8.1 installed.  See my prior posts for my process.  Others have said they tried to mirror it, but still crapped out on the upgrade.

I should mention that I finally did mine at 2am.  The server load on the Microsoft side might have something to do with it as well.  Just throwing it out there.

Still getting the same error here. I just don't get this idea of using (or not using ) WiFi and VPN. All the transmission protocols have their own error detection/correction and if this really was the issue then we would also be getting problems whenever we downloaded large files. It just seems to be this one file that causes the problem.

Why can't Microsoft just let us down load the file as an iso or zip? Its no use to anyone without a valid key so I don't get their reluctance. I've wasted countless Gigabytes of download bandwidth and still got nowhere,

Have done everything, everyone has suggested in this multi page thread. Same failure at the same point 50% every time.

Don't understand having to go through the store. Just give us a file.

I hate the Store.

Did you try downloading patch while connected through WiFi or through VPN? There is also some chance that you have memory errors or hard-drive issues, that creates situation that your file in memory does not give the right check sum. So if WiFi/VPN does not work, I would run memory tests.