wlan0 not detected: TP-Link TL-WN851ND / Ubuntu 10.10 / Compaq Presario SA4000T

[wrzomar]

I assume you mean /etc/modprobe.d/ath9k.conf.

Yes, that's exactly what I meant, but I think name is irrelevant - it must be any *.conf file inside /etc/modprobe.d/ or single lines in modprobe.conf (but I don't found one).

[chili555]

I think name is irrelevant - it must be any *.conf file inside /etc/modprobe.d/

Correct. It's just that naming it something relevant makes it easier to find later in case you want to undo it, modify it, refer to it in a forum post, etc. In my opinion, it's good practice for all kinds of files and folders.