I got a new PC with windows 7 64bit, my old E220 modem did not work (which I understand), so I got a new K3770 modem.
With the new modem, it connects, but it works for 2 secs and then there is no data being downloaded. I've tried a different modem and sim but get the same problem.
The old...
Have not tried this myself but... here goes... maybe someone can confirm for us...
http://www.webtlk.com/2008/06/04/enable-more-than-4-gb-of-ram-in-32-bit-windows-vista/