The title says it all. I had a machine here with a really old WLAN adapter (Realtek RTL-8185L on a PCMCIA card), and it wouldn’t connect to my local WLAN when using WPA-PSK2. I just checked that WLAN was working at all, and yes, it would connect without a pass-phrase, but with a key, it wouldn’t work. Each time, the authentication would simply fail due to a wrong password. The Linux was Ubuntu 9.10, but I guess it’ll be the same on other ones as well.
One weird issue was that the GNOME applet for entering the network key would refuse my 63 character key, and only let my type in 60 characters. Turns out that the problem is that for WPA-PSK, the key required to authenticate is not your pass-phrase, but generated from the pass-phrase and the SSID, and some drivers don’t do this transformation for you, so you have to help out by hand. That’s very easy, for instance by using wpa_passphrase. This gives you the PSK, and on entering this one instead of the pass-phrase, everything worked right away. Woho!
Just recently I had to fix a PC with Windows XP. It turned out that the installed version was not “genuine”. Du’h, someone helpful re-installed Windows on the machine, but instead of using the original OEM which came with the PC, he installed a retail XP with some key which was obviously invalid. I tried to change the product key to the valid one on the notebook (the one on the Windows sticker with the nice hologram), but the normal way to change keys refused it. Bummer. Called Microsoft, and it turned out that it’s an OEM key and the current Windows is not OEM (if you want to check, go to the control panel, system. If your system id is <….>-OEM, you’re on OEM)
Ok, so I had to change the XP version from retail to OEM, and then change the key somehow. Turns out that changing the XP version requires a reinstall — at least that’s what I was told by the Windows activation hotline operator. However, there is a different way, by using a tool from Microsoft to change the product key . Guess what, this tool was able to change the product key and the product version at the same time. Voilà, I had finally an OEM windows with a valid key, and could go ahead to install lots of updates as well as other tools that require a valid key like the pretty decent security essentials.
Machine is half-way fixed again; and I still wonder why computer science graduates are supposed to be good at troubleshooting Windows issues … and I’m always amazed how much crap people tend to install on their machines. Some good advice: If you install some stuff off the web, and you don’t use it/know what it is any more, remove it! And please try to keep your updates on; the machine in question had Firefox 2 and Adobe Reader 8, as well as a 4 year-old antivirus program. That’s basically a sure way to become a victim of some exploit.
So much for now, next week we’ll take a look at stupid WLAN drivers on Linux and WPA-PSK keys getting refused.
Starting today, I’m moving and won’t have internet access at home until at least mid-January. If you want to reach me, try via mail, I should be able to check at least once a day, but answers might take longer. I hope to finish moving by mid-February; with a bit of luck, I’ll have most stuff set up again in 2-3 weeks.
E-Mail, IM and other stuff is nice to get reached, but unfortunately, it’s also very time-consuming. Especially if E-Mail is (ab)used as a near-realtime communication system. In order to make it a bit more efficient, I’m changing my communication patterns a bit. I’ll try to check mails in a “best-effort” manner in the future, so no guarantees, and the timing is going to be like this. From Monday to Friday, I’ll try to check early in the morning (around 8-10) and once in the afternoon-early evening (15-18). IM presence will be reduced mostly to weekends and occasionally in the evening.
If there is something urgent, feel free to call me, or make an appointment. This is going to be much more effective than IM and E-Mail troubleshooting. For E-Mail, I actually analysed all my mail in the last year for “urgency”. There is not a single one which would have required a <24 hour response time, and most of the time <48 would have been sufficient. As I’m much faster during batch-processing mail, I’ve opted in for this new policy – which in turn should improve the answer quality 
, so it’s a win-win.
You shouldn’t expect an answer at all on weekends, even though I’ll try to check mail. I’m also no friend of exceptions, so if there is a deadline on Sunday – bad luck. The latter worked out very nicely so far, we managed for instance to have a paper finished several days in advance of the deadline, it’s all a matter of planning.