1. You will need to provide some more information about your unit.
a. the model number
b. the operating system you are using
c. are you connected to the router via a Ethernet cable on another computer?
d. Have you check with your ISP as to the status of the your connection.
e. Have you check the status of the router ( in the wireless settings) to see if the PC unit is getting a signal.
f. What is the wireless signal strength of the PC unit / Is it showing in the status bar of the Windows screen you are using.
g. Have you try to repair the connection via the PC you are connecting with wirelessly with. This can be done in the wireless connection icon in the task bar in Windows
I hope this helps. Please provide more information as to your issue.