This article was previously published under Q315244
When you map a network drive to a local share, the following error message may be reported in the system event log:
Event ID: 3019 Source: MRxSmb Description: The redirector failed to determine the connection type.
This behavior can occur when NetBIOS over TCP/IP (NetBT) attempts to query the destination device (in this case, the loopback adapter) for network speed. The loopback adapter does not handle speed negotiation and therefore cannot negotiate the speed.
This behavior is associated only with the TCP/IP protocol because TCP/IP is the only protocol that uses the Loopback adapter.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
This error message is only informational. You can safely ignore it.
This event is logged when you first connect to a mapped drive and create a new session with the server. The error message can appear when you create a network connection to a share on your local computer.
The event can occur in any of the following situations:
The first time that you connect to a mapped drive after you log on.
The first time that you connect to the mapped drive after the computer resumes from Hibernation mode.
The first time that you use a local network share after your computer is automatically disconnected from the mapped drive by using the autodisconnect feature.
Microsoft Windows XP Home Edition, Microsoft Windows XP Professional, Microsoft Windows XP Professional x64 Edition, Microsoft Windows Server 2003, Enterprise Edition (32-bit x86), Microsoft Windows Server 2003, Enterprise Edition for Itanium-based Systems, Microsoft Windows Server 2003, Enterprise x64 Edition, Microsoft Windows Server 2003, Standard Edition (32-bit x86), Microsoft Windows Server 2003, Standard x64 Edition