The problem is that the pc have 2 default gateways, 0.0.0.0 and a second (the real gateway) eg. 192.168.1.1 the problem occurs with some windows 7 pc´s with Adobe CS3 installed

The fix:
Windows 7 x64

1. Click Start, click Run, type cmd in the Open box, and then click OK.
2. Type: cd C:\Program Files (x86)\Bonjour\
3. Type: mDNSResponder.exe -remove
4. Type: rn mdnsNSP.dll mdnsNSP.dll.old
5. Reboot the pc