how to transfer files

Can anyone help me with file transfer between my PC and lapop?

I can do this before downloading MS SP2 and security mananger. However, in the windows explorer, my nextwork doesn't show those two istems in the workgroup. I suspect there must be something realated with MS security manager and firewall settings. But so far, I still can't work it out.... :(

I know someone here is huge NB on network, could you seerve me a hand?

Appreciated