Question : Problem: How to connect to lan on laptop?

I recently installed a loop back adapter on my laptop.From then onwards i was unable to connect to internet on my lan.Can anyone suggest me what to do?

Answer : Problem: How to connect to lan on laptop?

this could be solve by one of the following:
1- update your NIC driver
2- try another cable from your laptop to switch
3- reboot your switch
4- if this is DSL modem/switch try with another pc, it might be a problem in that modem "usually hanging"
5- make sure the power is good for your switch
6- from your NIC ->right click->properties-->configure-->advanced-->link speed Auto and try with 100, 10 full duplex