Article ID: 2686098 - View products that this article applies to.
After a Windows Server 2012-based or Windows 8-based computer fails to connect to a third-party file server that supports the SMBv2 file protocol, you receive one of the following error messages or a similar error message, depending on how you access the third-party file server:
This problem is caused by the "Secure Negotiate" feature that was added to SMB 3.0 for Windows Server 2012 and Windows 8. This feature depends upon the correct signing of error responses by all SMBv2 servers, including servers that support only protocol versions 2.0 and 2.1. Some third-party file servers do not return a signed error response. Therefore, the connection fails.
To resolve this problem, contact the third-party file server vendor to request an update that enables the file server to support Windows Server 2012 and Windows 8 clients.
Warning We do not recommend that you disable the requirement for secure negotiate, as this reduces computer security. Disable secure negotiate only as a temporary troubleshooting measure. Do not leave secure negotiate disabled; instead, contact the third-party file server vendor and request an update that allows their file server to support Windows Server 2012 and Windows 8 clients correctly.
For more information about the importance of secure negotiation, see http://blogs.msdn.com/b/openspecification/archive/2012/06/28/smb3-secure-dialect-negotiation.aspx
The ability to disable secure negotiate functionality may be removed in future operating systems.
To work around this problem, use either of the following methods:
For more information, click the following article number to view the article in the Microsoft Knowledge Base:
(https://support.microsoft.com/kb/2709568/ )New SMB 3.0 features in the Windows Server 2012 file server
Article ID: 2686098 - Last Review: March 2, 2015 - Revision: 12.0