After the Windows 2008 R2 64 bit server got below 2 updates a network share is no longer available. And trying to remap it with correct credentials (that work on a Windows 8.1 64 bit) gives this error: "System error 86 has occurred. The specified network password is not correct."
Local Policies -> Security Options -> Network Security: LAN Manager Authentication Level is already set to "LM and NTLM - use NTLMV2 session security if negotiated" - this is already done. In fact this is how it was working earlier. And it hasn't been changed.
Below 2 updates were installed in past few days:
Definition Update for Microsoft Endpoint Protection - KB2461484 (Definition 1.185.3528.0)
Installation date: 10/17/2014 4:22 PM
Installation status: Successful
Update type: Important
Install this update to revise the definition files that are used to detect viruses, spyware, and other potentially unwanted software. Once you have installed this item, it cannot be removed.
More information:
http://go.microsoft.com/fwlink/?LinkId=59048
Help and Support:
http://go.microsoft.com/fwlink/?LinkId=59048
Update for Windows (KB974405)
Installation date: 10/16/2014 10:25 AM
Installation status: Successful
Update type: Important
Windows Identity Foundation
More information:
http://support.microsoft.com?kbid=974405