Hi Francesco1975 ,
· Are you using a Wireless connection for the network or is it connected through Ethernet?
Step 1
You may also try to run the network troubleshooter built in Windows 7 and check if it finds any issues and if it is able to fix it.
http://windows.microsoft.com/en-US/windows7/Using-the-Network-troubleshooter-in-Windows-7
Step 2
If the issue persists, you may try to download the latest drivers from computer manufacturer’s website and save it on your desktop. Uninstall the ethernet card. While uninstalling the device from the device manager, make sure you follow the steps below:
a. Click on Start.
b. Access Control Panel > System > Hardware > Device Manager.
c. Open Device Manager and expand Network adapter.
d. Right click on the Network device installedand uninstall the same.
While uninstalling the device, make sure you place a check mark against "Delete the driver software for this device".
Restart the computer and reinstall the network adapter that you downloaded from the computer manufacturer’s website and check if it works fine.
Step 3
If uninstalling and reinstalling network adapter does not help, you may put the computer in a clean boot state and check if any third party services or application is causing this issue.
Access the link below and follow the steps to troubleshoot a problem by performing a clean boot in Windows Vista or in Windows 7.
http://support.microsoft.com/kb/929135
If your issue is resolved after performing Clean Boot, then follow the steps mentioned in the following KB article to narrow down the exact source.
Also, see the section on how return your computer to a Normal startup mode by following the steps under “Reset the computer to start as usual” and set it to Normal Startup.
Hope this helps. Let us know the results.
Thanks and Regards,
Srinivas R
Microsoft Support.
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