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I am creating a Login Form with a DataBase in Microsoft Access.
The DataBase: DataBase Photo
I am using Visual Studio 2015 Community Edition.
I have created 2 queries for this:
1) LoginQuery ->
SELECT        Username, [Password]
FROM            Login
WHERE        (Username = ?) AND ([Password] = ?)

2) EmployeeNameQuery ->
SELECT        EmployeeName, Username
FROM            Login
WHERE        (Username = ?)

While executing the code, if I enter both the Username and Password Correctly, I get the following error:
InvalidCastException was unhandled
An unhandled exception of type 'System.InvalidCastException' occurred in Microsoft.VisualBasic.dll
Additional information: Conversion from string "admin" to type 'Boolean' is not valid.

The Error: Error Photo

Else, for wrong inputs, it works and shows 'Invalid Login!'

What I have tried:

My Code:
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles Button1.Click
    Dim username As String = UsernameTextBox.Text
    Dim password As String = PasswordTextBox.Text
    If LoginTableAdapter.LoginQuery(username, password) Then
        Dim EmployeeName As String = LoginTableAdapter.EmployeeNameQuery(username)
        MsgBox("Login Successful!" & EmployeeName)
        MsgBox("Invalid Login!")
    End If
End Sub

-> Please explain it in detail because I have been facing this for quite a long time!
Updated 6-Nov-16 4:28am
[no name] 6-Nov-16 7:45am    
Explain what in detail? The error message is clear enough. Somewhere you are trying to use the string "admin" as if it were a Boolean value.
Arnav Varshney 6-Nov-16 10:27am    
But what should I correct so as to make it work @NotPoliticallyCorrect. That's what I meant by please explain in detail.
[no name] 6-Nov-16 15:16pm    
It's simple. Debug your code and find the place where you are using a string where the code is expecting a Boolean. Then fix it. The stack trace likely tells you exactly where the error is occurring.

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