WNetAddConnection2 returns 1312 : ERROR_NO_SUCH_LOGON_SESSION in 64 bit

Question

When I perform file upload to remote location using WNetAddConnection2, the file can be copied for the first time but next operation returns code 1312 with same user credentials. But after certain interval of time, the upload is successful again but
the next operation is returns same code.
I use the network connection as below:
public class NetworkConnection : IDisposable
string _networkName;
NetworkCredential _credentials;
public NetworkConnection(string networkName, NetworkCredential credentials)
_networkName = networkName;
_credentials = credentials;
var netResource = new NetResource()
Scope = ResourceScope.GlobalNetwork,
ResourceType = ResourceType.Disk,
DisplayType = ResourceDisplaytype.Share,
RemoteName = networkName
var userName = string.IsNullOrEmpty(credentials.Domain)
? credentials.UserName
: string.Format(@"{0}\{1}", credentials.Domain, credentials.UserName);
var result = WNetAddConnection2(
netResource,
credentials.Password,
userName,
0);
if (result != 0)
string strErrMsg = "";
if (result == 67)
strErrMsg = "The network name cannot be found.";
if (result == 86)
strErrMsg = "Invalid UserName or Password for server";
else if (result == 1219)
strErrMsg = "Multiple connections to a server or shared resource by the same user, using more than one user name, are not allowed.Close application to Disconnect all previous connections to the server or shared resource and try again.";
else if (result == 1312)
strErrMsg = "ERROR_NO_SUCH_LOGON_SESSION: A specified logon session does not exist. It may already have been terminated.";
throw new Win32Exception(result, "Error connecting to "+networkName+" remote share.Error Code:"+result.ToString()+"."+strErrMsg);
~NetworkConnection()
Dispose(false);
public void Dispose()
Dispose(true);
GC.SuppressFinalize(this);
protected virtual void Dispose(bool disposing)
WNetCancelConnection2(_networkName, 0, true);
[DllImport("mpr.dll")]
private static extern int WNetAddConnection2(NetResource netResource,
string password, string username, int flags);
[DllImport("mpr.dll")]
private static extern int WNetCancelConnection2(string name, int flags,
bool force);
[StructLayout(LayoutKind.Sequential)]
public class NetResource
public ResourceScope Scope;
public ResourceType ResourceType;
public ResourceDisplaytype DisplayType;
public int Usage;
public string LocalName;
public string RemoteName;
public string Comment;
public string Provider;
public enum ResourceScope : int
Connected = 1,
GlobalNetwork,
Remembered,
Recent,
Context
public enum ResourceType : int
Any = 0,
Disk = 1,
Print = 2,
Reserved = 8,
public enum ResourceDisplaytype : int
Generic = 0x0,
Domain = 0x01,
Server = 0x02,
Share = 0x03,
File = 0x04,
Group = 0x05,
Network = 0x06,
Root = 0x07,
Shareadmin = 0x08,
Directory = 0x09,
Tree = 0x0a,
Ndscontainer = 0x0b
Please let me know if I am missing something.
Is there anything i

Answer 1

Hi,
>>ERROR_NO_SUCH_LOGON_SESSION: A specified logon session does not exist. It may already have been terminated.
Which credential you used in WNetAddConnection2 function?
Services run (by default) under the built-in "Systtem" account. This account has very elevated rights on the local machine,but it has no network credentials (ie, it can connect only to remote shares that allow anonymous connections). You should either impersonnate
a user in your service or make the whole service run as a special, dedicated, account with the required credentials on the network.
>>the file can be copied for the first time but next operation returns code 1312 with same user credentials. But after certain interval of time, the upload is successful again but the next operation is returns same code.
I suggest you trying to dispose the NetworkConnection object ,and then new connection.
Regards,