Loss of Wireless Network Card/Adapter Function on Lenovo T420 upon resume:

On occasion my laptop loses wireless networking ability upon resume from suspend or hibernate. I do not understand why, and checking the hardware status reveals only an OS reply of "it's working fine!!!" But if you have the same problem, perhaps the following will be of assistance: I do warn you must have access rights to computer management, and that this may not (probably won't) solve every possible case!

1. Hit the "Start"/"Windows" button or else click on the "Start/Windows Menu" Icon.
2. In the resultant menu, right-click "Computer" and select "Manage".
3. In the left pane, select "Device Manager".
4. In the right pane, content appears. Select "Network Adapters" with a double-click, which will open the category by causing sub-items to flow-out; alternatively, just hit the arrow to its left, and the subitems will appear.
5. Select the name of your wireless network adapter (...yes, did I mention you need to know that? Er, no? Well it shouldn't say "virtual" (like "Microsoft Virtual Wifi Miniport Adapter"), "Bluetooth", or "Gigabit Network Connection", may include "Centrino", "Intel", "Broadcom", or other... sorry, can't be of much more help: see your manual, ask your manufacturer, etc.), right-click and choose "disable".
6. After a few moments wait, right-click the same item (as in 5.) again, and choose "enable".

That may solve your problem. After a moment check your network indicator icon in the system tray and see if you can see networks again, and connect to your network normally. If not...go look elsewhere for now!