My laptop has started to show steady data input and output as soon as it connects to the web via a wireless router. This continues for as long as I leave the machine connected. AVG 8, Ad-Aware and Spybot have revealed nothing.
Robert Caldicott

You are right to be concerned because the unknown data traffic could be spam or worse, if your PC has been hacked. However, the most likely cause is Microsoft’s Windows Update, which dribbles away in the background so as not to interfere with normal usage. Otherwise, your firewall should tell you which applications have your permission to access the internet, and which ones are active. Active processes should also be visible in the Windows Task Manager or the superior Process Explorer, a free download. In your case, the culprit may be setupxv.exe, which could be malware or fake anti-spyware.

The web is another common source of unknown data traffic. Some pages refresh adverts or update their contents periodically without telling you, but this should stop if you close down all browsers.

If you can’t see what’s sending traffic, you can try using a packet sniffer to capture and examine the data being transferred. Sadly, I use Wireshark (wireshark.org), which is not a simple option for beginners. There are alternatives listed at sectools.org and SnapFiles. SmartSniff looks easier to use. Other suggestions welcome!

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