Why is WLAN disabled? Acer Aspire 4520 Windows 7

Check Control Panel, System, Hardware, Device Manager and see if the wireless adapter is present or is yellow flagged as faulty.

fihart, thank you for your response. In Device Manager, the wireless adapter (Atheros) was not even present. But through sheer luck and persistence, I was able to fix this myself. The last time I had had success with the wireless was when the battery was in place. Now I use it plugged in and keep the battery in the refrigerator to try to extend its life. Since that was the only change I could think of, I put the battery back in and the wireless began to work again and the wireless adapters reappeared in Device Manager. Everything worked once I put the battery in and rebooted. Now I have taken the battery back out and put it back in the fridge and the wireless LAN is still working and the button toggles between "enable" and "disable". Nowhere on the Internet is this fix discussed and this fix makes no sense to me. But I recount it here in hopes it may help someone else with the same problem.

EPILOGUE:
The wireless LAN activation button worked swell for a time (for a week or so) after I retired the battery back to the refrigerator but now it is back to its same old tricks, i.e., (constantly) disabled. At least I know now I can get it to turn back on when I put the battery back in - hopefully - since I am not using the WiFi now. But what happens when the battery dies? I am told they don't last that long. Then I will have to buy a new battery just to activate the WiFi????? Sucks.

Best answer selected by cloudboy.