Thursday, 19 November 2009

Thursday, 12 November 2009

CMOS batteries ate my email



Maybe it's the cold weather, maybe it's a batch of duff CMOS batteries, but I'd advise all you PC-repair nerds to grab a spare CR2032 battery, on the off-chance that you get asked to investigate odd Firefox behaviour. I've had two call-outs in the last week, both from people who use webmail through Firefox, and were getting "This site's SSL certificate has expired" warnings. In both cases, the user's CMOS battery was weakening, meaning their PCs thought we were living either in the past, or in the future, which affected Firefox's ability to guess whether an SSL certificate is valid or not. Maybe Firefox uses the system time to check, and maybe if it does, it should use a web service to an atomic clock! Anyway, a new CMOS battery solved the problem, but it took a while to figure out that this was the root cause.