Winsock Error Codes

Article
11/18/2015

A version of this page is also available for

4/8/2010

The following list describes the possible error codes returned by WSAGetLastError in numerical order.

Value	Name	Description
10004	WSAEINTR	Interrupted function call. This error is returned when a socket is closed or a process is terminated, on a pending Winsock operation for that socket.
10013	WSAEACCES	Permission denied. An attempt was made to access a socket in a way forbidden by its access permissions.
10014	WSAEFAULT	Bad address. The system detected an invalid pointer address in attempting to use a pointer argument of a call. This error occurs if an application passes an invalid pointer value, or if the length of the buffer is too small. For instance, if the length of an argument, which is a sockaddr structure, is smaller than the sizeof(SOCKADDR).
10022	WSAEINVAL	Invalid argument. Some invalid argument was supplied (for example, specifying an invalid level to the setsockopt (Windows Sockets) function). In some instances, it also refers to the current state of the socket — for instance, calling accept (Windows Sockets) on a socket that is not listening.
10024	WSAEMFILE	Too many open files. Too many open sockets. Each implementation may have a maximum number of socket handles available, either globally, per process, or per thread.
10035	WSAEWOULDBLOCK	Resource temporarily unavailable. This error is returned from operations on nonblocking sockets that cannot be completed immediately, for example recv when no data is queued to be read from the socket. It is a nonfatal error, and the operation should be retried later. It is normal for WSAEWOULDBLOCK to be reported as the result from calling connect (Windows Sockets) on a nonblocking SOCK_STREAM socket, since some time must elapse for the connection to be established.
10036	WSAEINPROGRESS	Operation now in progress. A blocking operation is currently executing. Windows Sockets only allows a single blocking operation — per task or thread — to be outstanding, and if any other function call is made (whether or not it references that or any other socket) the function fails with the WSAEINPROGRESS error.
10037	WSAEALREADY	Operation already in progress. An operation was attempted on a nonblocking socket with an operation already in progress — that is, calling connect a second time on a nonblocking socket that is already connecting, or canceling an asynchronous request (WSAAsyncGetXbyY) that has already been canceled or completed.
10038	WSAENOTSOCK	Socket operation on nonsocket. An operation was attempted on something that is not a socket. Either the socket handle parameter did not reference a valid socket, or for the select function, a member of an fd_set structure was not valid.
10039	WSAEDESTADDRREQ	Destination address required. A required address was omitted from an operation on a socket. For example, this error is returned if sendto is called with the remote address of ADDR_ANY.
10040	WSAEMSGSIZE	Message too long. A message sent on a datagram socket was larger than the internal message buffer or some other network limit, or the buffer used to receive a datagram was smaller than the datagram itself.
10041	WSAEPROTOTYPE	Protocol wrong type for socket. A protocol was specified in the socket function call that does not support the semantics of the socket type requested. For example, the ARPA Internet UDP protocol cannot be specified with a socket type of SOCK_STREAM.
10042	WSAENOPROTOOPT	Bad protocol option. An unknown, invalid or unsupported option or level was specified in a getsockopt (Windows Sockets) or setsockopt (Windows Sockets) call.
10043	WSAEPROTONOSUPPORT	Protocol not supported. The requested protocol has not been configured into the system, or no implementation for it exists. For example, a socket call requests a SOCK_DGRAM socket, but specifies a stream protocol.
10044	WSAESOCKTNOSUPPORT	Socket type not supported. The support for the specified socket type does not exist in this address family. For example, the optional type SOCK_RAW might be selected in a socket call, and the implementation does not support SOCK_RAW sockets at all. Also, this error code maybe returned for SOCK_RAW if the caller application is not privileged.
10045	WSAEOPNOTSUPP	Operation not supported. The attempted operation is not supported for the type of object referenced. Usually this occurs when a socket descriptor to a socket that cannot support this operation is trying to accept a connection on a datagram socket.
10046	WSAEPFNOSUPPORT	Protocol family not supported. The protocol family has not been configured into the system or no implementation for it exists. This message has a slightly different meaning from WSAEAFNOSUPPORT. However, it is interchangeable in most cases, and all Windows Sockets functions that return one of these messages also specify WSAEAFNOSUPPORT.
10047	WSAEAFNOSUPPORT	Address family not supported by protocol family. An address incompatible with the requested protocol was used. All sockets are created with an associated address family (that is, AF_INET for Internet protocols) and a generic protocol type (that is, SOCK_STREAM). This error is returned if an incorrect protocol is explicitly requested in the socket call, or if an address of the wrong family is used for a socket, for example, in sendto.
10048	WSAEADDRINUSE	Address already in use. Typically, only one usage of each socket address (protocol/IP address/port) is permitted. This error occurs if an application attempts to bind a socket to an IP address/port that has already been used for an existing socket, or a socket that was not closed properly, or one that is still in the process of closing. For server applications that need to bind multiple sockets to the same port number, consider using setsockopt (Windows Sockets)(SO_REUSEADDR). Client applications usually need not call bind at all — connect chooses an unused port automatically. When bind is called with a wildcard address (involving ADDR_ANY), a WSAEADDRINUSE error could be delayed until the specific address is committed. This could happen with a call to another function later, including connect, listen, WSAConnect, or WSAJoinLeaf.
10049	WSAEADDRNOTAVAIL	Cannot assign requested address. The requested address is not valid in its context. This normally results from an attempt to bind to an address that is not valid for the local machine. This can also result from connect (Windows Sockets), sendto, WSAConnect, WSAJoinLeaf, or WSASendTo when the remote address or port is not valid for a remote machine (for example, address or port 0).
10050	WSAENETDOWN	Network is down. A socket operation encountered a dead network. This could indicate a serious failure of the network system (that is, the protocol stack that the Windows Sockets DLL runs over), the network interface, or the local network itself.
10051	WSAENETUNREACH	Network is unreachable. A socket operation was attempted to an unreachable network. This usually means the local software knows no route to reach the remote host.
10052	WSAENETRESET	Network dropped connection on reset. The connection has been broken due to keep-alive activity detecting a failure while the operation was in progress. It can also be returned by setsockopt (Windows Sockets) if an attempt is made to set SO_KEEPALIVE on a connection that has already failed.
10053	WSAECONNABORTED	Software caused connection abort. An established connection was aborted by the software in your host machine, possibly due to a data transmission time-out or protocol error.
10054	WSAECONNRESET	Connection reset by peer. An existing connection was forcibly closed by the remote host. This normally results if the peer application on the remote host is suddenly stopped, the host is rebooted, or the remote host uses a hard close (see setsockopt (Windows Sockets) for more information on the SO_LINGER option on the remote socket.) This error may also result if a connection was broken due to keep-alive activity detecting a failure while one or more operations are in progress. Operations that were in progress fail with WSAENETRESET. Subsequent operations fail with WSAECONNRESET.
10055	WSAENOBUFS	No buffer space available. An operation on a socket could not be performed because the system lacked sufficient buffer space or because a queue was full.
10056	WSAEISCONN	Socket is already connected. A connect request was made on an already-connected socket. Some implementations also return this error if sendto is called on a connected SOCK_DGRAM socket (for SOCK_STREAM sockets, the to parameter in sendto is ignored) although other implementations treat this as a legal occurrence.
10056	WSAEISCONN	Socket is already connected. A connect request was made on an already-connected socket. Some implementations also return this error if sendto is called on a connected SOCK_DGRAM socket (for SOCK_STREAM sockets, the to parameter in sendto is ignored) although other implementations treat this as a legal occurrence.
10057	WSAENOTCONN	Socket is not connected. A request to send or receive data was disallowed because the socket is not connected and (when sending on a datagram socket using sendto) no address was supplied. Any other type of operation might also return this error — for example, setsockopt (Windows Sockets) setting SO_KEEPALIVE if the connection has been reset.
10058	WSAESHUTDOWN	Cannot send after socket shutdown. A request to send or receive data was disallowed because the socket had already been shut down in that direction with a previous shutdown call. By calling shutdown a partial close of a socket is requested, which is a signal that sending or receiving, or both have been discontinued.
10060	WSAETIMEDOUT	Connection timed out. A connection attempt failed because the connected party did not properly respond after a period of time, or the established connection failed because the connected host has failed to respond.
10060	WSAETIMEDOUT	Connection timed out. A connection attempt failed because the connected party did not properly respond after a period of time, or the established connection failed because the connected host has failed to respond.
10061	WSAECONNREFUSED	Connection refused. No connection could be made because the target machine actively refused it. This usually results from trying to connect to a service that is inactive on the foreign host — that is, one with no server application running.
10064	WSAEHOSTDOWN	Host is down. A socket operation failed because the destination host is down. A socket operation encountered a dead host. Networking activity on the local host has not been initiated. These conditions are more likely to be indicated by the error WSAETIMEDOUT.
10065	WSAEHOSTUNREACH	No route to host. A socket operation was attempted to an unreachable host. See WSAENETUNREACH.
10067	WSAEPROCLIM	Too many processes. A Windows Sockets implementation may have a limit on the number of applications that can use it simultaneously. WSAStartup may fail with this error if the limit has been reached.
10091	WSASYSNOTREADY	Network subsystem is unavailable. This error is returned by WSAStartup if the Windows Sockets implementation cannot function at because the underlying system it uses to provide network services is currently unavailable. Users should check: That the appropriate Windows Sockets DLL file is in the current path. That they are not trying to use more than one Windows Sockets implementation simultaneously. If there is more than one Winsock DLL on your system, be sure the first one in the path is appropriate for the network subsystem currently loaded. The Windows Sockets implementation documentation to be sure all necessary components are currently installed and configured correctly.
10092	WSAVERNOTSUPPORTED	Winsock.dll version out of range. The current Windows Sockets implementation does not support the Windows Sockets specification version requested by the application. Check that no old Windows Sockets DLL files are being accessed.
10093	WSANOTINITIALISED	Successful WSAStartup not yet performed. Either the application has not called WSAStartup or WSAStartup failed. The application may be accessing a socket that the current active task does not own (that is, trying to share a socket between tasks), or WSACleanup has been called too many times.
10101	WSAEDISCON	Graceful shutdown in progress. Returned by WSARecv and WSARecvFrom to indicate that the remote party has initiated a graceful shutdown sequence.
10109	WSATYPE_NOT_FOUND	Class type not found. The specified class was not found.
11001	WSAHOST_NOT_FOUND	Host not found. No such host is known. The name is not an official host name or alias, or it cannot be found in the database(s) being queried. This error may also be returned for protocol and service queries, and means that the specified name could not be found in the relevant database.
11002	WSATRY_AGAIN	Nonauthoritative host not found. This is usually a temporary error during host name resolution and means that the local server did not receive a response from an authoritative server. A retry at some time later may be successful.
11003	WSANO_RECOVERY	This is a nonrecoverable error. This indicates some sort of nonrecoverable error occurred during a database lookup. This may be because the database files (for example, BSD-compatible HOSTS, SERVICES, or PROTOCOLS files) could not be found, or a DNS request was returned by the server with a severe error.
11004	WSANO_DATA	Valid name, no data record of requested type. The requested name is valid and was found in the database, but it does not have the correct associated data being resolved for.
OS dependent	WSA_INVALID_HANDLE	Specified event object handle is invalid. An application attempts to use an event object, but the specified handle is not valid.
OS dependent	WSA_INVALID_PARAMETER	One or more parameters are invalid. An application used a Windows Sockets function, which directly maps to a Win32 function. The Win32 function is indicating a problem with one or more parameters.
OS dependent	WSA_IO_INCOMPLETE	Overlapped I/O event object not in signaled state. The application has tried to determine the status of an overlapped operation, which is not yet completed. Applications that use WSAGetOverlappedResult (with the fWait parameter set to FALSE) in a polling mode to determine when an overlapped operation has completed, get this error code until the operation is complete.
OS dependent	WSA_IO_PENDING	Overlapped operations will complete later. The application has initiated an overlapped operation that cannot be completed immediately. A completion indication will be given later when the operation has been completed.
OS dependent	WSA_NOT_ENOUGH_MEMORY	Insufficient memory available. An application used a Windows Sockets function that directly maps to a Win32 function. The Win32 function is indicating a lack of required memory resources.
OS dependent	WSA_OPERATION_ABORTED	Overlapped operation aborted. An overlapped operation was canceled due to the closure of the socket, or the execution of the SIO_FLUSH command in WSAIoctl.
OS dependent	WSAINVALIDPROCTABLE	Invalid procedure table from service provider. A service provider returned a bogus procedure table to Ws32.dll. (Usually caused by if one or more of the function pointers is null.)
OS dependent	WSAINVALIDPROVIDER	Invalid service provider version number. A service provider returned a version number other than 2.0.
OS dependent	WSAPROVIDERFAILEDINIT	Unable to initialize a service provider. Either a service provider's DLL could not be loaded (LoadLibrary failed) or the provider's WSPStartup/ NSPStartup function failed.

Winsock Error Codes

See Also

Reference

Additional resources