Q: macbook pro wifi connection suddenly stopped

Hey wiendelt,

Thanks for the question. After reviewing your post, it sounds like the computer isn't recognizing hardware in the computer. I would recommend that you read these articles, they may be able to help you resolve or isolate the issue.

Intel-based Macs: Resetting the System Management Controller (SMC)

http://support.apple.com/kb/HT3964

Wi-Fi: How to troubleshoot Wi-Fi connectivity

http://support.apple.com/kb/HT4628?viewlocale=en_US

If your Wi-Fi interface does not appear in System Preferences, then you'll need to make sure that your Wi-Fi card is recognized by your Mac. Start from the installation media that came with your computer, or from theRecovery HD if OS X Lion is installed. Your computer should be able to access available networks.

Thanks for using Apple Support Communities.

Have a nice day,

Mario