"Couldn't update to Windows 8.1 - 0xC1900101 - 0x40017"

At least try uninstalling whatever security system and then do the update, followed by re-installing

the security system - after so many tries it can't hurt. 

What Microsoft Techs should be aware of is to at least ask if Avast is on the computer and then

proceed.  Shameful that Microsoft does not acknowledge at least this problem.

Yes it finally works

During multiple failed updates i noticed an error flashing by after the first restart, to fast to read :-(

With a Lucky hit on the pauze button i managed to read it.

"not enough memory to create a ram drive"

My old pc only has only 2 Gb of ram, and i already disabled en uninstalled everything i could.

I also use the onboard videocard and this card uses a part of system ram.

I installed an old videocard and disabled the onboard videocard and the allocated memory in bios setup.

and now it works, hopefully i can help someone with this info.

Grts

Leo :-)

Hello to everyone on this post. After experiencing this error and scrolling through dozens of pages I finally found page 75 with members reporting success after removing Avast . Thank you to all.  It worked after removing Avast Internet security. Perhaps Avast need a big hint that they need to do something about their product.

I noticed quite a bit of Microsoft bashing in this post it goes to show that you shouldn't jump to conclusions before it has been worked on.

Sorry, I disagree with you.  Myself and many others do not use Avast and have not been able to upgrade to 8.1.  This has been going on for many months without any meaningful support or recognition of the problem from Microsoft.  I could go on about this but I'll simply say they deserve the criticism that has been voiced on this forum.

And I wouldn't be so quick to say Avast is to blame, they didn't develop the 8.1 upgrade.  I see it as Microsoft's responsibility to test their software and so state in their release notes a problem installing with other popular  products.  This they have not done to date that I know of.  They won't even acknowledge that an installation problem exists.

The real problem is not Avast.

I couldn't agree more with you. It beggars belief that Microsoft engineers haven't got to grips with this fundamental issue. Worryingly for the corporation's marketing types, many patient non-techy types like myself, loyal to Microsoft for many years,  are likely to give up the ghost with the whole Windows 8 fiasco and move to Apple.

hi 

i have asus ultra book pro and nothing extra is connected to laptop. (i7, 8 gb Ram )

i already installed 8.1 which worked fine then. 

now after i reinstalled windows 8 successfully and wished to upgrade to 8.1 i am getting same error message. 

i installed all necessary updates and additional option updates before going for 8.1 . but still problem persists. 

suggest