I got trouble of connecting to the shared folder from Win2k recently from my laptop, Win7. I found this guide below on how to successfully connect to the server.
Click the start button and type secpol.msc in the search function.
Browse to "Local Policies" -> "Security Options". Now look for
the entry "Network Security: LAN Manager authentication level" and open
it. Click on the dropdown menu and select "Send LM & NTLM - use
NTLMv2 session security if negotiated". Apply the settings.