Each of the children have a desktop, two laptops, and an iPhone. I have two desktops, two laptops, an iPhone, and a Droid. I also have four running servers here at the house, two PlayStation 3's a Sony connected multimedia Blu-Ray player, Chromecast, the garage Powermac, and any number of virtual machines, all connected through the same router.
We are running collectively, in no particular order:
iOS
OSX
Android
Windows 7
Windows 8.1
openSUSE 12.3
openSUSE 13.2
HP/UX
CellOS
Yet my daughter's 8.1 laptop can ping external domain names (both internet and DNS is working) and Windows Update works, but applications cannot reach their update servers and none of the browsers can reach anything
even if given an internal IP address! Can you imagine the expression on my face when the Windows Network Troubleshooter told me it couldn't identify the problem in connecting to a private IP? And I do use that term loosely. Windows Network Troubleshooter, since its inception, has been unable to solve any of my networking dilemmas, ever. I have no idea why they continue to roll it out with every version of windows. Possibly to alert some furrowed-brow Facebook-poster that the reason they are disallowed from accessing the internet is because their laptop is powered off or something to that effect. Her laptop can ping google.com, but can't connect to the gateway IP address in a browser (or a private webserver running on an alternate port).
What hasn't helped is any combination of netsh, Set-NetIPInterface, using built-in wi-fi, wired ethernet and even a USB wireless interface (though I assume the only people suggesting that have no knowledge of networking), turning off the firewall, disabling anti-virus (really?), running anti-malware and trojan killers (which I really was hoping was the culprit), deleting and recreating the devices, updating the drivers, rebooting the router (I know, I know), and sfc /scannow (although I credit sfc /scannow with the ability to finally install malwwarebytes which previously failed with
Could not call proc) or even hardcoding the interfaces with static values.
Despite this rampant asininity, I learned how to create an Administrator account on Windows 8.1 (not that it afforded the authority to take ownership of system files - or let me delete files already owned by administrator) and how to boot into safe mode (shift-restart) <- because F8 would have been too simple. Although Win8.1 disallows IE from being launched as Administrator - which is fantastically hysterical. And by fantastically hysterical of course I mean astonishingly frightening. I can think of a handful of reasons for this, none of which are complementary.

This command will place an Administrator account on your Win8.1 box
Afterwhich you should be able to force ownership and deletion (although I ran this in recovery mode cli):
takeown /F C:\{troublesome_folder}\* /R /A
rmdir /S /Q C:\{troublesome_folder}\
But I was surprised to discover that launching regedit in a recovery console doesn't give you the system's registry, rather what looks like the recovery console's registry? Which wouldn't be a big deal except the registry editor disallows certain keys to be deleted by the Administrator when logged in as Administrator. But of course it does. So I decided to see if I could
telnet to the web port on my internal server, and that's when I discovered telnet was no longer installed on Windows. No idea when that happened, but a quick double-click of putty and a new error helped me troubleshoot -
Unable to initialise WinSock <-- Yes, with the British spelling.
Deleting the following keys from the registry, then rebooting...
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Winsock
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Winsock2
...got me to a new error to troubleshoot,
Socket type not supported (once again using putty), but also disabled DNS. To re-enable, I had to find, then download winsock.inf (because I couldn't find it anywhere on the computer). This is here for my future enjoyment of Win8:

winsock.inf
Another reboot (for the winsock) but still no browser access -
and windows network troubleshooter can now tell me my ethernet connection has no configuration, but it can't tell me WHY - even when the IP, netmask, gw, and DNS are all hardcoded...and now I have a "limited" connection on both wi-fi and cabled ethernet because with the reset, her laptop thought she was on a public network. The "why" of this is my fault, coupled with the nonsensical judgments of Microsoft. The reason her network connection is considered "public" is because I opted to not share folders and printers, and the ONLY REASON anyone would EVER CHOOSE to NOT SHARE is if they were on a public network, right? Which is why I found it so difficult to revert back to private - it makes no goddamn sense. But figuring this one out was as easy as Google, whereas applying the change was far less transparent. The obtuse calisthenics one needs to go through in order to change from "Public" to "Private" is a veritable cathedral of dumb, requiring modifying the Local Security Policy, which is apparently unavailable on certain "editions" of Windows 8.1 in what I assume is a hidden nomenclature of appended Home/Premium/Ultimate/Professional/Enterprise, and obviously not one which comes preloaded on a $300 Asus notebook for a 10-year old girl. Because she would never need to modify her Local Security Policy, right? It just works? So, back to the registry! Only...the registry already had the correct value (1) for a Private connection in the DWORD - oh noes - endless rabbithole is endless!

In conclusion, I'm considering a "refresh" which is less horrific than a "reinstall" but utterly mired in layers upon layers of asininity, most of which I already assume will introduce far more problems than are corrected.
I will understand if my daughter hates me. I hate me right now too.