3 days ago I went out and bought myself a new present - a Huawei E5830 modem. This is a mobile broadband device that turns a mobile signal into a wifi signal and provides you with your own personal wifi hotspot wherever you are (providing there is a mobile broadband signal of course). I bought it so that my wife and myself can simultaneously share a mobile internet connection when we are away from home (it connects up to 5 devices apparently). It was therefore required to work on 2 machines, her laptop and mine. On my machine (fairly modern) it worked like a dream - I am using it now. But getting it to work on her (old) laptop nearly gave me a nervous breakdown. I have spent 2 days mired in wifi misery!
I have spent all that time tearing down and building up wireless connections, I have upgraded and downgraded network managers, I have switched network managers, then switched back again when the one I changed to was as bad than the one I already had, I have disabled firewalls, I have flushed iptables, I have flashed firmware, I have changed encryption, I have messed with command line tricks that have more in common with witchcraft than computing, I have edited /network/interfaces, I even booted Windows (took about 10 minutes but it connected of course), I have pinged, I might even have ponged, I don't know . All I do know is that the only answer I ever got was "network unreachable". Incidentally, I was using Crunchbang Lite which is about the only thing that I can persuade to work on my wife's laptop.
Last thing last night after spending all day on this I had an idea to run the Crunchbang live cd on her machine and see what happened. What happened was it connected straight away . So then I had another idea - reinstall the OS. As this machine is only used when we are away from home,and it belongs to my wife who mainly uses Windows anyway there was not much configuration involved in reinstalling, but the main thing is - it worked So why? My answer is that some update or other rendered the thing incapable of connecting to wifi.
That leads me on nicely to the next part of my title. I use Sidux as well as Mint and others. Just recently they updated Network-Manager-Gnome to version 0.7.999-2. This version completely stuffed nearly all my internet connections (it could still work with wired, but everything else was gone). I downgraded to 0.7.2-2 and got everything back again, but the warning mentioned in the title relates to this NM version - DO NOT use it in its present form.