สอบถามเมื่อจะทำการ connect เข้่าสู่ระบบไม่ได้เกิด error คำว่า the connectionString property has not been intialized

Imports System
Imports System.Data
Imports System.Data.SqlClient

Module ModSys

    Public Declare Auto Function GetSystemMenu Lib "user32" (ByVal hwnd As IntPtr, ByVal bRevert As Int32) As IntPtr
    Public Declare Auto Function RemoveMenu Lib "user32" (ByVal hMenu As IntPtr, ByVal nPosition As Int32, ByVal wFlags As Int32) As Int32
    Public Const MF_REMOVE As Int32 = &H1000&
    Public Const MF_BYPOSITION As Int32 = &H400&

    Public gConn As New SqlConnection
    Public gStrcn As String
    Public sServName, sUser, sPass As String
    Public Const sLabel = "Mobile City Co.,Ltd."
    Public sqlNumIm As String
    Public sqlNumSA As String
    Public tmpProID, tmpProN As String
    Public tmpProIDOr, tmpProNOr As String
    Public tmpSale, tmpCost, tmpSaleS, ctmpSale As Long
    Public tmpPINShop, tmpPINOr, ctmpINShop As Integer
    Public tmpSuppID, tmpSuppN As String
    Public tmpUserName As String
    Public bhIDor, bhIDSa, bhIDSaCre As String
    Public tmpCustID, tmpCustN, tmpSex, tmpIDCard, tmpAddr, tmpTel As String
    Public tmpProIDSa, tmpProNSa As String
    Public ctmpProID, ctmpProN As String
    Public strPath As String
    Public tOrderID, tSaleID, tSaleCreID As String


    Public Function DbConnect() As Boolean

        On Error GoTo error_handle
        Dim gConn As SqlConnection



        'If gConn.State = ConnectionState.Closed Then
        'gConn = New SqlConnection
        'With gConn
        '.ConnectionString = "Data Source=mint-nb;Catalog=account;User Id=sa;Password=123456"
        'Integrated Security=True"
        '.ConnectionString = "Data Source=orcl_ao.hcwml.com;User Id=sak;Password=tc123456"
        'gConn.Open()

        'MsgBox("Connection Complete", vbOKOnly + vbInformation, "CONNECTION")
        'End With
        'End If

        'gConn = New System.Data .Sql .
        gConn = New SqlConnection
        gConn.ConnectionString = "Data Source=ACER-PC;Initial Catalog=account;User Id=sa;Password=p@ssw0rd"
        DbConnect = True
        Exit Function
error_handle:
        MsgBox(Err.Description & Chr(10) & "Error: Can not connect to database" & _
            "Please contact administrator", _
            vbOKOnly, "ConnectDB Error")
        DbConnect = False
    End Function
End Module