can't update to 8.1 0xc1900101-0x20017

That is an absolute lie.  The box and and laptop both had stickers on them that said "Upgrade to windows 8 Free!"  That was a MAJOR selling point to the laptop...

To all owners of the ASUS U43F laptop.

Here is what the tech support from ASUS told me about this laptop:

"We apologize for any inconvenience or frustration this may have caused. The reason you are having issues updating is this unit does not support 8.1 or 10. It was designed and we only claim it supports windows 7. So if you were able to install 8, thats more than what we claim it will support. We deeply apologize for this matter, but this unit does not appear it will have windows 10 support. "

They have no intentions of helping or solving the upgrade issue with these laptops. We are stuck with what it is!!!

I, too, am an owner of the Asus U43F. I have been trying to update to Windows 8.1 and Windows 10 since 2013. I bought this computer back in 2011 and didn't expect its lifespan would end so abruptly. Funny enough, my Asus A8H from 2007 is able to install Windows 10, whereas my Asus U43F is not. I have contacted Asus Tech Support on multiple occasions for help on this issue. They flat out said that because your computer came with Windows 7 we are under no obligation to help you on any other operating system besides that. I have ran Microsoft's Upgrade Asssitant and it has stated that my computer was compatible with an upgrade to Windows 10. If I knew my computer would not be able to upgrade past Windows 8 I would not have purchased this $700 computer. I have felt cheated and lied to by Asus and will most likely not purchase their products again, because I simply cannot be certain if their products will be supported in the future.. I will be switching to Apple's Mac and avoid the headache that comes with Microsoft and PCs. It has been a good run, but 2 years of trying and failing to install Windows on this computer has left me fustrated.

I CAN confirm this.  Sad...I work really hard for my money and this laptop is basically useless with Windows 8 on it.  I just do not have $700 to burn whenever I feel like it.  I guess no more ASUS or Microsoft products for me and I have been a purchaser/user since 1985.

Bad news for all Asus U43F users. With the release of Windows 10, the update fails with the same BSOD error as with Windows 8.1, "DRIVER_VIOLATION". Seems as though the life of this laptop stops with Windows 8.