That's not an easy question to answer. And it is also puzzling that it can't hit the internet unless you are using VPN to actually connect. It's possible that your router isn't connecting/logging into your ISP.
You may want to reset your router to it's default settings and see if you can get back into the internet. It's entirely possible that your ISP had changed the way it would like their subscribers to log in, thus you may have to reset your router accordingly.
Another possibility would be that it could be a fimrware/software or hardware fault within your router. If the former, you may need to update the firmware of your router. Look up your router's maufacturing web site if they have the latest firmware upgrades. Usually, they would. If it's the latter, you may need to replace it (assuming that you dont have extended warranty on it).
Also hardware related, your broadband modem maybe on it's way out as well....either software or hardware. If so, then the same thing would apply.
It may also be something as simple as a 'bad' CAT 5 cable that connects your router to the broadband modem.
I hope that this helps alittle and good luck.
My wife and I have a laptop that receives a strong wireless signal but receives no internet connection.
Here are some possible clues:
1) cannot ping any addresses other than router
2) can connect to internet but only using school VPN account
This problem occurred only recently; we were able to use the laptop within our home wireless network for well over a year (without logging onto VPN).
Suggestions? I just wish I could pinpoint the problem (i.e., laptop? router?).