Strange problem with two identical Lenovo Z370's (well one pink, one black). The pink one always connects, the black one sometimes fails to connect - it just reports a generic connection failed error. Tried reinstalling drivers, deleting wireless settings, removing anti-virus/security.
It also fails on other wireless networks, so its not down to the router. Both laptops had dentical drivers - the AR9285 v220.127.116.114 dated 12 Aug 2010 (Windows 7 64 bit) which is the latest that Lenovo list for that model. I also tried imaging the laptop from pink to black - but same problem, which started me thinking it was a hardware fault.
However before I went down that route I spotted an updated HP driver for the AR9285, which seemed to go as high as 18.104.22.1684 for the EliteBook 6930p. Having a good search around the Lenovo site uncovered a 22.214.171.124 dated 24 Nov 2010 for a Lenovo G470 (also available for the IdeaPad Z570)
I had to run the installer twice (first time uninstalls) and then the laptop connected immediately.
Wireless connects reliably now.