title: Application crash for unknown reasons on WinXP
body: <p>I have Delphi XE3, Windows 7 Pro 64bit.
  My application is working fine in my PC but my users told me application crashes upon start on their Win XP and also (!!) on their Win 7.</p>
  
  <p>I tried to run the app on my Win 7 but logged as an ordinary user (no admin) - it works.
  So now I have installed virtual machine with Windows XP and really - app crashes upon startup.</p>
  
  <p>I need to find what can be the problem but I'm helpless.</p>
  
  <p>As far as I can't use debugger (I dont have Delphi on that VM installed),
  I tried to put some <code>MessageBox(0, 'Hello', 'Test', MB_OK);</code> in various places in my app to catch the place where it happens and this is what I found:</p>
  
  <p>I have this in my project-source:</p>
  
  <pre><code>MessageBox(0, 'Hello', 'Test', MB_OK); // shows OK
  Application.CreateForm(TfMain, fMain);
  MessageBox(0, 'Hello', 'Test', MB_OK); // doesn't show - crash before this line
  </code></pre>
  
  <p>And this is in the <code>OnCreate</code> function of my main form called <code>fMain</code>:</p>
  
  <pre><code>procedure TfMain.FormCreate(Sender: TObject);
  begin
    MessageBox(0, 'Hello', 'Test', MB_OK); // doesn't show - crash before this line
    ...
  </code></pre>
  
  <p>So where can this app crash?<br>
  Not even first line in the <code>OnCreate</code> executes....<br>
  I have no idea... Anybody?</p>
  
  <p>Don't know if this is important: I have some units in fMain <code>uses</code> clause under <code>interface</code> and also under <code>implementation</code>. Should I look there? But what happens just before <code>OnCreate</code> of my main form ?</p>