Have you tried connecting your netbook to the next via WiFi to see if you can access PTS? If you still cann't try clearing the history, cookies and offline files from your browser? Sometimes a piece of data from the previous days uses can cause problems.
If you can access PTS via WiFi, then I would recommend disabling the WiFi, ethernet and bluetooth adaptors on your netbook. Then try accessing PTS using your SIM. Somestimes the WiFim ethernet and bluetooth adaptors can cause problems with the SIM adaptor.