Why won't the applications on my computer connect to the internet?

[Aeronautical]

Check in your Firewall (in control panel under security) or your anti-virus program (such as norton,mcafee etc) for blocked programs, which means they are prevented from getting data packets from your router (ie no internet access). A few may be blocked for whatever reason but your whole antivirus or firewall may be switched into a mode where all inbound/outbound connections are rejected (which makes more sense since a lot of your programs are not getting a connection). Alternatively your wireless reciever on your computer (or wired connection) may not be very good and consequently you may not have internet access.

Hope this helps, good luck.