WNetAddConnection2A function (winnetwk.h)
The WNetAddConnection2 function makes a connection to a network resource and can redirect a local device to the network resource.
The WNetAddConnection2 function supersedes the WNetAddConnection function. If you can pass a handle to a window that the provider of network resources can use as an owner window for dialog boxes, call the WNetAddConnection3 function instead.
Syntax
DWORD WNetAddConnection2A(
[in] LPNETRESOURCEA lpNetResource,
[in] LPCSTR lpPassword,
[in] LPCSTR lpUserName,
[in] DWORD dwFlags
);
Parameters
[in] lpNetResource
A pointer to a NETRESOURCE structure that specifies details of the proposed connection, such as information about the network resource, the local device, and the network resource provider.
You must specify the following members of the NETRESOURCE structure.
The WNetAddConnection2 function ignores the other members of the NETRESOURCE structure.
[in] lpPassword
A pointer to a constant null-terminated string that specifies a password to be used in making the network connection.
If lpPassword is NULL, the function uses the current default password associated with the user specified by the lpUserName parameter.
If lpPassword points to an empty string, the function does not use a password.
If the connection fails because of an invalid password and the CONNECT_INTERACTIVE value is set in the dwFlags parameter, the function displays a dialog box asking the user to type the password.
Windows Me/98/95: This parameter must be NULL or an empty string.
[in] lpUserName
A pointer to a constant null-terminated string that specifies a user name for making the connection.
If lpUserName is NULL, the function uses the default user name. (The user context for the process provides the default user name.)
The lpUserName parameter is specified when users want to connect to a network resource for which they have been assigned a user name or account other than the default user name or account.
The user-name string represents a security context. It may be specific to a network provider.
Windows Me/98/95: This parameter must be NULL or an empty string.
[in] dwFlags
A set of connection options. The possible values for the connection options are defined in the Winnetwk.h header file. The following values can currently be used.
| Value | Meaning |
|---|---|
|
The network resource connection should be remembered.
If this bit flag is set, the operating system automatically attempts to restore the connection when the user logs on. The operating system remembers only successful connections that redirect local devices. It does not remember connections that are unsuccessful or deviceless connections. (A deviceless connection occurs when the lpLocalName member is NULL or points to an empty string.) If this bit flag is clear, the operating system does not try to restore the connection when the user logs on. |
|
The network resource connection should not be put in the recent connection list.
If this flag is set and the connection is successfully added, the network resource connection will be put in the recent connection list only if it has a redirected local device associated with it. |
|
The network resource connection should not be remembered.
If this flag is set, the operating system will not attempt to restore the connection when the user logs on again. |
|
If this flag is set, the operating system may interact with the user for authentication purposes. |
|
This flag instructs the system not to use any default settings for user names or passwords without offering the user the opportunity to supply an alternative. This flag is ignored unless CONNECT_INTERACTIVE is also set. |
|
This flag forces the redirection of a local device when making the connection.
If the lpLocalName member of NETRESOURCE specifies a local device to redirect, this flag has no effect, because the operating system still attempts to redirect the specified device. When the operating system automatically chooses a local device, the dwType member must not be equal to RESOURCETYPE_ANY. If this flag is not set, a local device is automatically chosen for redirection only if the network requires a local device to be redirected. Windows Server 2003 and Windows XP: When the system automatically assigns network drive letters, letters are assigned beginning with Z:, then Y:, and ending with C:. This reduces collision between per-logon drive letters (such as network drive letters) and global drive letters (such as disk drives). Note that earlier versions of Windows assigned drive letters beginning with C: and ending with Z:. |
|
If this flag is set, then the operating system does not start to use a new media to try to establish the connection (initiate a new dial up connection, for example). |
|
If this flag is set, the operating system prompts the user for authentication using the command line instead of a graphical user interface (GUI). This flag is ignored unless CONNECT_INTERACTIVE is also set.
Windows XP: This value is supported on Windows XP and later. |
|
If this flag is set, and the operating system prompts for a credential, the credential should be saved by the credential manager. If the credential manager is disabled for the caller's logon session, or if the network provider does not support saving credentials, this flag is ignored. This flag is ignored unless CONNECT_INTERACTIVE is also set. This flag is also ignored unless you set the CONNECT_COMMANDLINE flag.
Windows XP: This value is supported on Windows XP and later. |
|
If this flag is set, and the operating system prompts for a credential, the credential is reset by the credential manager. If the credential manager is disabled for the caller's logon session, or if the network provider does not support saving credentials, this flag is ignored. This flag is also ignored unless you set the CONNECT_COMMANDLINE flag.
Windows Vista: This value is supported on Windows Vista and later. |
Return value
If the function succeeds, the return value is NO_ERROR.
If the function fails, the return value can be one of the following error codes or one of the system error codes.
| Return code | Description |
|---|---|
|
The caller does not have access to the network resource. |
|
The local device specified by the lpLocalName member is already connected to a network resource. |
|
The type of local device and the type of network resource do not match. |
|
The specified device name is not valid. This error is returned if the lpLocalName member of the NETRESOURCE structure pointed to by the lpNetResource parameter specifies a device that is not redirectable. |
|
The network name cannot be found. This value is returned if the lpRemoteName member of the NETRESOURCE structure pointed to by the lpNetResource parameter specifies a resource that is not acceptable to any network resource provider, either because the resource name is empty, not valid, or because the named resource cannot be located. |
|
The user profile is in an incorrect format. |
|
The specified network provider name is not valid. This error is returned if the lpProvider member of the NETRESOURCE structure pointed to by the lpNetResource parameter specifies a value that does not match any network provider. |
|
The specified user name is not valid. |
|
The router or provider is busy, possibly initializing. The caller should retry. |
|
The attempt to make the connection was canceled by the user through a dialog box from one of the network resource providers, or by a called resource. |
|
The system is unable to open the user profile to process persistent connections. |
|
The local device name has a remembered connection to another network resource. This error is returned if an entry for the device specified by lpLocalName member of the NETRESOURCE structure pointed to by the lpNetResource parameter specifies a value that is already in the user profile for a different connection than that specified in the lpNetResource parameter. |
|
A network-specific error occurred. Call the WNetGetLastError function to obtain a description of the error. |
|
An attempt was made to access an invalid address. This error is returned if the dwFlags parameter specifies a value of CONNECT_REDIRECT, but the lpLocalName member of the NETRESOURCE structure pointed to by the lpNetResource parameter was unspecified. |
|
A parameter is incorrect. This error is returned if the dwType member of the NETRESOURCE structure pointed to by the lpNetResource parameter specifies a value other than RESOURCETYPE_DISK, RESOURCETYPE_PRINT, or RESOURCETYPE_ANY. This error is also returned if the dwFlags parameter specifies an incorrect or unknown value. |
|
The specified password is invalid and the CONNECT_INTERACTIVE flag is not set. |
|
A logon failure because of an unknown user name or a bad password. |
|
No network provider accepted the given network path. This error is returned if no network provider recognized the lpRemoteName member of the NETRESOURCE structure pointed to by the lpNetResource parameter. |
|
The network is unavailable. |
|
Use FormatMessage to obtain the message string for the returned error. |
Remarks
On Windows Server 2003 and Windows XP, the WNet functions create and delete network drive letters in the MS-DOS device namespace associated with a logon session because MS-DOS devices are identified by AuthenticationID (a
locally unique identifier, or LUID, associated with a logon session.) This can affect applications that call one of the WNet functions to create a network drive letter under one user logon, but query for existing network drive letters under a different user logon. An example of this situation could be when a user's second logon is created within a logon session, for example, by calling the
CreateProcessAsUser function, and the second logon runs an application that calls the
GetLogicalDrives function. The call to the GetLogicalDrives function does not return network drive letters created by WNet function calls under the first logon. Note that in the preceding example the first logon session still exists, and the example could apply to any logon session, including a Terminal Services session. For more information, see
Defining an MS-DOS Device Name.
On Windows Server 2003 and Windows XP, if a service that runs as LocalSystem calls the WNetAddConnection2 function, then the mapped drive is visible to all user logon sessions.
For Microsoft network providers, the lpRemoteName member of the NETRESOURCE structure pointed to by the lpNetResource parameter can contain an IPv4 address in dotted-decimal notation. An example for a share might be the following:
\192.168.1.1\share
For Microsoft network providers on Windows Vista and later, the lpRemoteName member of the NETRESOURCE structure pointed to by the lpNetResource parameter can contain an IPv6 address. However, the IPv6 literal format must be used so that the IPv6 address is parsed correctly. An IPv6 literal address is of the form:
ipv6-address with the ':' characters replaced by '-' characters followed by the ".ipv6-literal.net" string.
For example, for the following IPv6 address:
2001:4898:9:3:c069:aa97:fe76:2449
an example for a share might be the following:
\2001-4898-9-3-c069-aa97-fe76-2449.ipv6-literal.net\share
Other network providers may support the lpRemoteName member of the NETRESOURCE structure pointed to by the lpNetResource parameter that contains an IPv4 or IPv6 address, but this is up to specific network provider.
Windows 7 and Windows Server 2008 R2: If the WNetAddConnection2 function is called with explicit user credentials specified in the pUsername and lpPassword to establish a connection with a network resource on a specific server and then called again with either of these parameters as NULL (to use the default user name or default password) to the same server, the call with fail. The error returned will be ERROR_BAD_USERNAME or ERROR_INVALID_PASSWORD.
Examples
The following code sample illustrates how to use the WNetAddConnection2 function to make connection to a network resource.
#ifndef UNICODE
#define UNICODE
#endif
#pragma comment(lib, "mpr.lib")
#include <windows.h>
#include <tchar.h>
#include <stdio.h>
#include <Winnetwk.h>
// Need to link with Netapi32.lib and Mpr.lib
int wmain(int argc, wchar_t * argv[])
{
DWORD dwRetVal;
NETRESOURCE nr;
DWORD dwFlags;
if (argc != 5) {
wprintf(L"Usage: %s <localname> <remotename> <username> <password>\n",
argv[0]);
wprintf(L" %s X: \\\\contoso\\public testuser testpasswd\n",
argv[0]);
exit(1);
}
wprintf(L"Calling WNetAddConnection2 with\n");
wprintf(L" lpLocalName = %s\n", argv[1]);
wprintf(L" lpRemoteName = %s\n", argv[2]);
wprintf(L" lpUsername = %s\n", argv[3]);
wprintf(L" lpPassword = %s\n", argv[4]);
// Zero out the NETRESOURCE struct
memset(&nr, 0, sizeof (NETRESOURCE));
// Assign our values to the NETRESOURCE structure.
nr.dwType = RESOURCETYPE_ANY;
nr.lpLocalName = argv[1];
nr.lpRemoteName = argv[2];
nr.lpProvider = NULL;
// Assign a value to the connection options
dwFlags = CONNECT_UPDATE_PROFILE;
//
// Call the WNetAddConnection2 function to assign
// a drive letter to the share.
//
dwRetVal = WNetAddConnection2(&nr, argv[4], argv[3], dwFlags);
//
// If the call succeeds, inform the user; otherwise,
// print the error.
//
if (dwRetVal == NO_ERROR)
wprintf(L"Connection added to %s\n", nr.lpRemoteName);
else
wprintf(L"WNetAddConnection2 failed with error: %u\n", dwRetVal);
exit(1);
}
For other code samples that illustrates how to make a connection to a network resource using the WNetAddConnection2 function, see Adding a Network Connection and Assigning a Drive to a Share.
Note
The winnetwk.h header defines WNetAddConnection2 as an alias that automatically selects the ANSI or Unicode version of this function based on the definition of the UNICODE preprocessor constant. Mixing usage of the encoding-neutral alias with code that is not encoding-neutral can lead to mismatches that result in compilation or runtime errors. For more information, see Conventions for Function Prototypes.
Requirements
| Requirement | Value |
|---|---|
| Minimum supported client | Windows 2000 Professional [desktop apps only] |
| Minimum supported server | Windows 2000 Server [desktop apps only] |
| Target Platform | Windows |
| Header | winnetwk.h |
| Library | Mpr.lib |
| DLL | Mpr.dll |