I tend to stay fairly close to the bleeding edge when it comes to personal technology. For instance, while it seems to freak people out, I have been using Windows 8 since it was in public beta release more than a year ago.
When the 8.1 update to was released last week, I naturally installed it the very first day on three different computers. Personally, the installs were trouble-free on all three machines, though I set them to automatically download and install Windows updates, which made made that installation easier for me than it could have been (there are Windows updates that must be installed prior to the 8.1 update, and the 8.1 update will now show up for you if you don't do that step first).
Last night, however, I did encounter a networking issue related to Windows 8.1, which appears to be a fairly wide-spread issue (lots of talk about it online already in forums, so many people are seeing similar issues). I noticed that, after I woke my machine from sleep, it almost immediately lost internet connectivity (actually, network connectivity of all types, since it couldn't even see the local network printers). I temporarily regained access by disabling the network card and connecting via wifi, but that was erratic as well. I had to disable and enable network cards several times to get enough online search time to troubleshoot. Here are my two suggestions for how to deal with this.
First, roll back the driver on your network card to an earlier version. For many, just reading that was probably very terrifying. Here's how to do it:
You can do this by going to device manager, right click on your network
adapter, go to update driver, then "browse my computer for driver
software, then"let me pick from a list of...." , uncheck the "show
compatible hardware" checkbox and finally select the older version of
current driver (if you dont know which, just use trial and error).
Hat tip to Technet. Let me elaborate. Right click in the lower left hand corner of your screen, where the new Windows start screen icon now sits. This brings up the power user menu. Click on Device Manager. Expand the portion of the device list showing "Network adapters." My machine has several, including an ethernet card and a wi-fi adapter. Right click on the adapter giving you trouble. Select update driver. Follow the instructions above (browse my computer for driver...then choose let me pick from a list). In my case, I had 3 drivers, one labelled a "Microsoft" driver and two from the card manufacturer. I selected one from the manufacturer and installed that one. The installation of a manufacturer driver has fixed my problem for the last day.
Now, for a more robust solution, when you are in the Device manager, take note of the name of your network adapter (including any model number) for ethernet and/or wifi. Search online (if you can get there) for that manufacturer's website. Look for a support/downloads menu option and try to find current downloads. I found drivers updated for Windows 8.1 for both of my adapters that way (I haven't installed them yet, since my rollback fix is working for now and I have work to finish). The newest manufacturer drivers should replace any glitchy drivers added during setup.
As an aside, this seems to be something that manufacturers knew was coming, since Dell pulled all of the BIOS files for my computer about a week ago and then released an updated BIOS a few days ago that had unspecified changes to networking compatibility in its change log. Interesting... I installed the updated BIOS and so far everything is behaving.
If you stumble on this post while pulling your hair out over networking problems, I hope it helps.