I've been on the forum for weeks trying, like many others, to find a solution for the networking failure. I've tried EVERY suggestion, more than once or twice, and I've been very close to just do the ugly re-boot(camp)ing thing. I think Parallels Desktop is a terrific piece of software, and I really couldn't understand how the makers could be failing so horribly. And now it turns out that, at least in my configuration, it's really not Parallels' fault. So what did I do? I turned off the Kaspersky security. Completely. And my XP is back online!! Of course, if you have self-assigned IP-addresses or similar trouble, you'll have to fix that first - as described in multiple threads here - but to me the correctly assigned IPs still didn't mean that my VM was networking. But now it is. I'm assuming that Kaspersky is still partly useable, it's probably just the firewall part that's causing the problems, but I decided on drastic measures. I'll r-implement Kaspersky step-by-step to see what will happen. I really hope this will help some people, since I know how frustrated you all are.
Strange thing, though, is that in OSX Network Preferences, both Parallels-related items are switched OFF. (I forgot to turn them back on after the umpteenth try). I can now confirm it IS just the Kaspersky firewall causing trouble. Evrything else is back on. And I am running Parallels release 5600, by the way, without hassle.
Johan, Thank you so much for this fix. Kaspersky must have really clamped down in a recent update! I, too, was suffering from IE not being able to display any sites. AND, the only reason we use Parallels is to use a website than only runs on IE Windows. So, IP addresses and DHCP all worked well. Windows said my network was working properly, but IE did not think so. Disabling Kaspersky did the trick. But I have been able to put some of the tools back to work without ill affect. I will keep playing with it to see which of the protection tools is causing the problem. Once again, thank so much.