If you happen to be experiencing network connectivity issues in Windows 7 then this troubleshooting guide from Microsoft can be very handy in getting to the bottom of it.
This tutorial is designed to help you identify and fix network connection problems in Windows. This tutorial doesn’t cover network connection problems related to specific programs. Network connection problems can be caused by cables that aren’t connected properly, corrupt drivers, incompatible drivers, network connection settings, missing updates, and hardware or software problems.
Not only can you follow along with this troubleshooter online but there is a XPS and PDF version of it that can be printed out and used offline while working on the connectivity problems.