1511 to 1607 Update Error 0x800700c1

PeterAstle · 02 Oct 2016

I have Windows 10 Pro Version 1511, OS Build 10586.589.

Windows continually attempts to download and install the anniversary upgrade.
The download completes, but the installation fails with error code 0x800700c1.
This has happened more than 50 times.
(As appears quite common, I have never experienced an update error before.)

I have tried every suggested fix I can find - nothing works.
I have tried installing from 1607 ISO - fails
I have tried installing using Windows10Upgrade28084.exe - fails
I have tried letting Microsoft Support have a go - fails

I am unable to find the meaning of the error code above, so there seems to be no way to effect action here.
Does anybody have any knowledge on this one?

dalchina · 02 Oct 2016

Hi, I can understand the frustration.

Now given that you've tried 'every suggested fix' it's bound to be the case that if someone suggests sthg you'll come back and say 'tried that', given that you've not stated what you have tried.

Here are some initial ideas:
1. From an admin command prompt
[Windows key + X, click command prompt (admin)]
chkdsk C: /F
Your PC will need to restart.
Make sure the result is clear or fixed- else do not proceed.
Post back the result, which you can get after a restart as follows:
How do I see the results of a CHKDSK that ran on boot? - Ask Leo!

2. Do a clean boot and disable any AV. Disconnect any unnecessary peripheral. Make sure you have at least 500Mb of unallocated space on your system disk. Make sure you have 20Gb + 10Gb free on your system partition.

Then try the manual upgrade. Don't try to download further updates if offered.

3. Inspect setup error logs
Win 10 AU upgrade:
Hopefully you’ll see a log here: C:\$WINDOWS.~BT\Sources\Panther\setuperr.log

4. Check if your BITS service is running.

PeterAstle · 04 Oct 2016

:) Thanks for your time and your suggestions.
I didn't get around to trying them because on the 63rd attempt, Windows successfully installed the update.
There was no input from me at all - it just happened.
So the software was downloaded literally 63 times before this process completed.
Only glad I'm not paying by the minute!

dalchina · 05 Oct 2016

Goodness me..! That's a lot of download time.. I'd have opted for the manual root after a couple of attempts.

Now, be warned.. there are then several updates, two large and problematical for a number - download problems mostly. For fixes, please see the thread about that update in the News section here.

1511 to 1607 Update Error 0x800700c1

1511 to 1607 Update Error 0x800700c1

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