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'Internet - How to check whether the system is connected with internet (in two ways)
'Method 1:

Option Explicit
 
Private Declare Function InternetGetConnectedState Lib "wininet.dll" (ByRef lpSFlags As Long, _
    ByVal dwReserved As Long) As Long
'return True if there is an active Internect connection

Public Function IsConnectedToInternet() As Long
    Dim flags As Long
    ' this ASPI function does it all
    InternetGetConnectedState flags, 0
    IsConnectedToInternet = flags
End Function
'How can I call this function:
'Debug.Print IsConnectedToInternet > 0

'Method 2:

Option Explicit
 
Public Declare Function RasEnumConnections Lib "RasApi32.dll" Alias "RasEnumConnectionsA" _
    (lpRasCon As Any, lpcb As Long, lpcConnections As Long) As Long
Public Declare Function RasGetConnectStatus Lib "RasApi32.dll" Alias "RasGetConnectStatusA" _
    (ByVal hRasCon As Long, lpStatus As Any) As Long
 
Private Const RAS95_MaxEntryName = 256
Private Const RAS95_MaxDeviceType = 16
Private Const RAS95_MaxDeviceName = 32
 
Public Type RASCONN95
    dwSize As Long
    hRasCon As Long
    szEntryName(RAS95_MaxEntryName) As Byte
    szDeviceType(RAS95_MaxDeviceType) As Byte
    szDeviceName(RAS95_MaxDeviceName) As Byte
End Type
 
Public Type RASCONNSTATUS95
    dwSize As Long
    RasConnState As Long
    dwError As Long
    szDeviceType(RAS95_MaxDeviceType) As Byte
    szDeviceName(RAS95_MaxDeviceName) As Byte
End Type
 
Public Function IsConnected() As Boolean
    Dim TRasCon(255) As RASCONN95
    Dim lg As Long
    Dim lpcon As Long
    Dim RetVal As Long
    Dim Tstatus As RASCONNSTATUS95
 
    TRasCon(0).dwSize = 412
    lg = 256 * TRasCon(0).dwSize
 
    RetVal = RasEnumConnections(TRasCon(0), lg, lpcon)
    If RetVal <> 0 Then
        MsgBox "ERROR"
        Exit Function
    End If
 
    Tstatus.dwSize = 160
    RetVal = RasGetConnectStatus(TRasCon(0).hRasCon, Tstatus)
    If Tstatus.RasConnState = &H2000 Then
        IsConnected = True
    Else
        IsConnected = False
    End If
End Function