Thanks, Radster
1I had the same problem with my Toshiba Satellite after upgrading from Win 8 to 8.1 and installing the Windows 8.1 update and the other Windows updates this week.
This is what worked for me (so far- 6 hours without a problem):
- open Control Panel> Device Manager
- click on Network Adapters
- select the adapter (wireless, ethernet, etc) that is giving you the problems
- Right-click and select Properties
- click the Driver tab and select Update Driver
- Choose the option to let you select the driver manually. DO NOT choose to let Windows automatically select the driver.
- If another screen comes up offering to let you Pick From a List of Drivers on your computer, choose that.
- Choose an older version of the driver from the manufacturer of your adapter. It is likely to be showing the manufacturer name rather than Microsoft; the newest version probably shows Microsoft. For me, it had to be a driver dated prior to October 2013. (You won't see the date until after you select a new driver and then look at the Properties tab again)
This has solved my problem at least for now. At some point I plan to go the manufacturer's website to look for new, 8.1 compatible adapter. But I'm leaving well enough alone for the moment since things are working OK.
Credit to H. Scott Leviant for suggesting this procedure: