I have a ThinkPad X200 with Debian Stretch installed, but the wifi icon does not show up and only wired connection works. So I ran , which put a bunch of .ucode files like the following into /lib/firmware/:

After reboot, wifi still doesn't work. I ran and it comes up empty. I then ran and got two additional messages in dmesg:
Below these two messages there is nothing. Normally some messages should come after these two messages indicating either the success or failure of the loading of iwlwifi firmware...

I'm at a loss here. Any help would be appreciated. Thanks in advance.

Let's start at the beginning.

Run lspci, and lsusb as root, and check for the wifi. If it shows on lspci, forget firmware - it has it. If it doesn't show on either, but you think it should be on usb, that's when you need wifi firmware. Vista Business was the Windows? The one that was going to solve everything for Microsoft (Windows 8) was out 2012, wasn't it? :-)). So your box is not exactly new.

Tell us are you using sysV or NetworkManager also. Some distros have an option for both.

Hi,

Stupid question but, is there any switch to disable wifi ?

Yes - loads. Getting it working is trickier.

You can turn it off in the BIOS (probably), load a kernel without support6 or remove the module. You can decomission it in software (ifdown,rfkill).

After disassembling the laptop and looking under the hood, we determined that it was a hardware problem. Thanks guys.

Good enough. Merk this solved then.