Alexey, Your problem sounds like a network hardware/driver/stack issue. Things to try include: - Reinstall SP4 - Reinstalling the latest network drivers for your card.(*) - Removing the card and reinstalling the whole network stack.(*) - Replacing the network card. (*) In these cases, you will need to reinstall SP4 once you've replaced the driver/stack. Wez @ RealVNC Ltd.