First, please do not post new questions in existing threads someone else started, unless they are directly relevant to the discussion in the thread. Starting a new thread is much beter. Second, be careful not to double post when you submit your messages. Third, please try to be as clear in your writing as possible, using proper grammar and punctuation as best to your ability.
To address the question you seem to be asking, I'll start by asking, did you use an import ctypes directive before trying to access that library? You always have to import all libraries you are trying to use before using them. Also, user32 is itself a sub-library; you would want to call a specific function from that library such as MessageBoxW() in order to get anything done with it.
Dim Adapter As New OleDbDataAdapter
Dim Command As New OleDbCommand
Dim xFrom As String = dtpFrom.Value.ToString.Substring(0, dtpFrom.Value.ToString.IndexOf(" "))
Dim xTo As String = dtpTo.Value.ToString.Substring(0, dtpTo.Value.ToString.IndexOf(" "))
sqlQuery = MainQuery ...