WNetGetLastError

The WNetGetLastError function retrieves the most recent extended error code set by a Windows network function.

DWORD WNetGetLastError(
  LPDWORD lpError,     // pointer to error code
  LPTSTR lpErrorBuf,   // pointer to string describing error
  DWORD nErrorBufSize, // size of description buffer, in characters
  LPTSTR lpNameBuf,    // pointer to buffer for provider name
  DWORD nNameBufSize   // size of provider name buffer
);
 

Parameters

lpError

Points to the variable that receives the error code reported by the network provider. The error code is specific to the network provider.

lpErrorBuf

Points to the buffer that receives the null-terminated string describing the error.

nErrorBufSize

Specifies the size, in characters, of the buffer pointed to by the lpErrorBuf parameter. If the buffer is too small for the error string, the string is truncated but still null-terminated. A buffer of at least 256 characters is recommended.

lpNameBuf

Points to the buffer that receives the null-terminated string identifying the network provider that raised the error.

nNameBufSize

Specifies the size, in characters, of the buffer pointed to by the lpNameBuf parameter. If the buffer is too small for the error string, the string is truncated but still null-terminated.

Return Values

If the function successfully obtains the last error reported by the provider, the return value is NO_ERROR. If the caller supplies an invalid buffer, it is ERROR_INVALID_ADDRESS.

Remarks

WNetGetLastError is used to obtain errors that are specific to a network provider. It should be used when a Windows network function (or the GetLastError function) returns ERROR_EXTENDED_ERROR. Like GetLastError, the function returns extended error information, which is maintained on a per-thread basis. Unlike GetLastError, the WNetGetLastError function can also return a string for reporting errors that are not described by any existing error code.

QuickInfo

  Windows NT: Use version 3.1 or later.
  Windows: Use Windows 95 or later.
  Windows CE: Unsupported.
  Header: Declared in winnetwk.h.
  Import Library: Use mpr.lib.

See Also

Windows Networking (WNet) Overview, Windows Networking Functions, GetLastError