The following table is a list of possible error codes returned by the WSAGetLastError() call, along with their explanations.
| Windows Sockets | Code | Error Description |
| WSAEINTR | 10004 | Interrupted system call. |
| WSAEBADF | 10009 | Bad file number. |
| WSEACCES | 10013 | Permission denied. |
| WSAEFAULT | 10014 | Bad address. |
| WSAEINVAL | 10022 | Invalid argument. |
| WSAEMFILE | 10024 | Too many open files. |
| WSAEWOULDBLOCK | 10035 | Operation would block. |
| WSAEINPROGRESS | 10036 | Operation now in progress. This error is |
| returned if any Windows Sockets API | ||
| function is called while a blocking | ||
| function is in progress. | ||
| WSAEALREADY | 10037 | Operation already in progress. |
| WSAENOTSOCK | 10038 | Socket operation on nonsocket. |
| WSAEDESTADDRREQ | 10039 | Destination address required. |
| WSAEMSGSIZE | 10040 | Message too long. |
| WSAEPROTOTYPE | 10041 | Protocol wrong type for socket. |
| WSAENOPROTOOPT | 10042 | Protocol not available. |
| WSAEPROTONOSUPPORT | 10043 | Protocol not supported. |
| WSAESOCKTNOSUPPORT | 10044 | Socket type not supported. |
| WSAEOPNOTSUPP | 10045 | Operation not supported on socket. |
| WSAEPFNOSUPPORT | 10046 | Protocol family not supported. |
| WSAEAFNOSUPPORT | 10047 | Address family not supported by protocol |
| family. | ||
| WSAEADDRINUSE | 10048 | Address already in use. |
| WSAEADDRNOTAVAIL | 10049 | Cannot assign requested address. |
| WSAENETDOWN | 10050 | Network is down. This error may be |
| reported at any time if the Windows | ||
| Sockets implementation detects an | ||
| underlying failure. | ||
| WSAENETUNREACH | 10051 | Network is unreachable. |
| WSAENETRESET | 10052 | Network dropped connection on reset. |
| WSAECONNABORTED | 10053 | Software caused connection abort. |
| WSAECONNRESET | 10054 | Connection reset by peer. |
| WSAENOBUFS | 10055 | No buffer space available. |
| WSAEISCONN | 10056 | Socket is already connected. |
| WSAENOTCONN | 10057 | Socket is not connected. |
| WSAESHUTDOWN | 10058 | Cannot send after socket shutdown. |
| WSAETOOMANYREFS | 10059 | Too many references: cannot splice. |
| WSAETIMEDOUT | 10060 | Connection timed out. |
| WSAECONNREFUSED | 10061 | Connection refused. |
| WSAELOOP | 10062 | Too many levels of symbolic links. |
| WSAENAMETOOLONG | 10063 | File name too long. |
| WSAEHOSTDOWN | 10064 | Host is down. |
| WSAEHOSTUNREACH | 10065 | No route to host. |
| WSASYSNOTREADY | 10091 | Returned by WSAStartup(), indicating that |
| the network subsystem is unusable. | ||
| WSAVERNOTSUPPORTED | 10092 | Returned by WSAStartup(), indicating that |
| the Windows Sockets DLL cannot support | ||
| this application. | ||
| WSANOTINITIALISED | 10093 | Winsock not initialized. This message is |
| returned by any function except | ||
| WSAStartup(), indicating that a | ||
| successful WSAStartup() has not yet been | ||
| performed. | ||
| WSAEDISCON | 10101 | Disconnect. |
| WSAHOST_NOT_FOUND | 11001 | Host not found. This message indicates |
| that the key (name, address, and so on) | ||
| was not found. | ||
| WSATRY_AGAIN | 11002 | Nonauthoritative host not found. This |
| error may suggest that the name service | ||
| itself is not functioning. | ||
| WSANO_RECOVERY | 11003 | Nonrecoverable error. This error may |
| suggest that the name service itself is | ||
| not functioning. | ||
| WSANO_DATA | 11004 | Valid name, no data record of requested |
| type. This error indicates that the key | ||
| (name, address, and so on) was not found. |