I am unable to connect my co-worker computer since I install windows 7.I am using router and switch for the internet access.And I have adsl internet.Do you guys have gone through this problem.
Is the other machine on?

How are you trying to connect?
Have you check the physical connection to you router/switch (ie is the cable plugged in)?
Are you able to ping the default gateway?
" " other computer?
Are these machines on the same subnet?
Are you using a VPN or something to take effect?
You say connect are you meaning a windows shared drive?
Have you remapped the drive?
Do you know how to map the drive from one machine to another?
Is the share still shared?
Are you on a Windows Domain or Workgroup?
What type of error messages are you getting (if any)?
Need input please...