connection help requested

i had a complete wireless network set up at home. PC in study with ethernet modem and seperate MIMO router laptop that connects through the router. Had a problem with the PC and had to re-format and re-install all software. Since then cannot connect to internet through PC. Still have internet through laptop (wireless) but cannot work out why PC wont connect. Have no network connections, though when i try to use connction wizard, it wont finish as it says i already have a broadband connection established.
I am foxed :?: :?:

Any help gratefully recieved.