Win 7 Can't Login to Windows Sharing

There is a PC with newly installed Windows 7.
The computer failed to be connected to my office's file server on Windows 2003.
The server keep fail to authenticate the computer and the computer keep asking for user name and password.

The solution:

• 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.

      Jonathan Ravzin (MCT - Microsoft Certified Trainer)
      URL: http://social.technet.microsoft.com/Forums/en-US/w7itpronetworking/thread/68ffbe2a-09a7-4e29-859c-ca1aaf75dcd1/