Password changer

$server = InputBox(@ScriptName, "Please enter target server.", "")
If @error = 1 Then Exit
$user = InputBox(@ScriptName, "Please enter your user name.", "")
If @error = 1 Then Exit
$old_password = InputBox(@ScriptName, "Please enter your old password.", "", "*M")
If @error = 1 Then Exit
$new_password = InputBox(@ScriptName, "Please enter your new password.", "", "*M")
If @error = 1 Then Exit
CONNECT()
; **** This line does not get reached if any of the input values are wrong??? ****
If @error Then MsgBox (0, @ScriptName, "Connection failed, error code = " & @error & ". Outside function.")

;************************************************************* FUNCTION DECLARATION ********************************************************
Func CONNECT()
$conn = ObjCreate("ADODB.Connection")
$conn.ConnectionString = "DRIVER={SQL Server};SERVER=" & $server & ";DATABASE=master;UID=" & $user & ";PWD=" & $old_password & ";"
$conn.ConnectionTimeout = 30
$conn.Open
; **** This line does not get reached if any of the input values are wrong??? ****
If @error Then MsgBox (0, @ScriptName, "Connection failed, error code = " & @error & ". Inside function.")
$conn.CommandTimeout = 600
$conn.Execute("ALTER LOGIN [" & $user & "] WITH PASSWORD=N'" & $new_password & "' OLD_PASSWORD=N'" & $old_password & "'")
$conn.Close
EndFunc