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Q: How can I share files between workgroup computer and domain/workgroup
computer?
I have a home wireless network and share files and a printer between two
computers.  I also use Win 2000/XP  laptop at work with domain network. How
can I share files between these computers at home?

A: Deepening on your network setup, you may 1) Logon local laptop using the
same logon id and password on both machine.
2) change workgroup name to match win2000 domain and the laptop needs to
install at home first ad then join the domain .
3) without changing the workgroup name and logon ID, just enable guest
account in win 2000/XP.
4)  If you are running XP, enable Simple File Sharing.
5) logon domain user on the domain laptop (even the workgroup is different),
use command net use \\workgroupcomputer /user:administrator, (here
administrator is workgroup computer local administrator), the enter
workgroup computer administrator password. You should be able to access the
workgroup resources.

Easy. Always log into the domain, even when offline. No need to create a
local account, even.

Once you have an IP address on the network at home, and can ping the other
computers (by name/IP address both), you can map drives, share printers,
etc.

For example, in a command prompt:

net use x: \\computer\share /user:computer\username <enter>