Can`t Connect To The Internet

Hi, 

I own a Dell N5040, which I use mainly for browsing the web and playing a few games on. About a week ago, I started having problems connecting to my internet network. I would connect to the network, and a yellow triangle would show up. Upon opening the network centre, it would say "no internet access" I can use the internet with no issues in safe mode with networking. 

My Specs are: 

Windows 7 64-Bit 

Intel Pentium P6200 @ 2.13ghz  

4gb RAM 

500gb HDD 

Thanks in advance.