I have covered this before but because of recent changes to Vista (sp1) I have had to redo my LAN security to connect to shares on a local Buffalo Teratation. It looks like its these older devices only that are affected as my new Linux server and a new Terastation Pro 2 dont have this problem.
SO: If you have difficulty logging onto an older terastation with Vista try the following:
Click “Start -> Run.” Then, type in the Run field: “secpol.msc.” That will bring you to Vista’s security policy system. Once there, use “Go to: Local Policies > Security Options” and then find “Network Security: LAN Manager” authentication level. Once there, change the Setting from “Send NTLMv2 response only” to “Send LM & NTLM — use NTLMv2 session security if negotiated.”