WNetGetLastError function

The WNetGetLastError function retrieves the most recent extended error code set by a WNet function. The network provider reported this error code; it will not generally be one of the errors included in the SDK header file WinError.h.

Syntax

DWORD WNetGetLastError(
  _Out_ LPDWORD lpError,
  _Out_ LPTSTR  lpErrorBuf,
  _In_  DWORD   nErrorBufSize,
  _Out_ LPTSTR  lpNameBuf,
  _In_  DWORD   nNameBufSize
);

Parameters

lpError [out]

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

lpErrorBuf [out]

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

nErrorBufSize [in]

Size of the buffer pointed to by the lpErrorBuf parameter, in characters. 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 [out]

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

nNameBufSize [in]

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

Return value

If the function succeeds, and it obtains the last error that the network provider reported, the return value is NO_ERROR.

If the caller supplies an invalid buffer, the return value is ERROR_INVALID_ADDRESS.

Remarks

The WNetGetLastError function retrieves errors that are specific to a network provider. You can call WNetGetLastError when a WNet function returns ERROR_EXTENDED_ERROR.

Like the GetLastError function, WNetGetLastError returns extended error information, which is maintained on a per-thread basis. Unlike GetLastError, the WNetGetLastError function can return a string for reporting errors that are not described by any existing error code in WinError.h.

For more information about using an application-defined error handler that calls the WNetGetLastError function, see Retrieving Network Errors.

Requirements

See also

Windows Networking (WNet) Overview

Windows Networking Functions