Application crash for unknown reasons on WinXP - delphi

Question

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.
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.
I need to find what can be the problem but I'm helpless.
As far as I can't use debugger (I dont have Delphi on that VM installed),
I tried to put some MessageBox(0, 'Hello', 'Test', MB_OK); in various places in my app to catch the place where it happens and this is what I found:
I have this in my project-source:
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
And this is in the OnCreate function of my main form called fMain:
procedure TfMain.FormCreate(Sender: TObject);
begin
MessageBox(0, 'Hello', 'Test', MB_OK); // doesn't show - crash before this line
...
So where can this app crash?
Not even first line in the OnCreate executes....
I have no idea... Anybody?
Don't know if this is important: I have some units in fMain uses clause under interface and also under implementation. Should I look there? But what happens just before OnCreate of my main form ?

Answer 1

Finally I got it !
place PRINT DIALOG component on your form (TPrintDialog)
set COPIES = 1 (or more than default zero) in the object inspector during design time
try to run such application on WinXP where NO PRINTERS are installed
Application just crashes upon start and in the details you will see only some kernel32.dll address...
I didn't test it on Win 7 without printers. I have no such system around...

Answer 2

Here's another way to track this down without Delphi on the VM...
Copy your project.
Remove all the units from Project Source except your main form.
Launch your application from XP see if it crashes.
If it crashes...then look at the units being dragged in from your main form...start removing them until your program stops crashing.
If it doesn't crash...start adding units/forms back into your project source until it crashes.
Do you have JCL/JVCL installed(JEDI)?
If so create a Logger...note the Logger needs to be created and hooked before your MainForm code executes...You will also need to set up a detailed Stack Trace from Unhandled Exceptions,
in Delphi select->Project/Options/Linker/Map file/Detailed}
You will need something like this in your Logger unit
procedure HookGlobalException(ExceptObj: TObject; ExceptAddr: Pointer; OSException: Boolean);
var
a_List: TStringList;
begin
if Assigned(TLogger._Instance) then
begin
a_List := TStringList.Create;
try
a_List.Add(cStar);
a_List.Add(Format('{ Exception - %s }', [Exception(ExceptObj).Message]));
JclLastExceptStackListToStrings(a_List, False, True, True, False);
a_List.Add(cStar);
// save the error with stack log to file
TLogger._Instance.AddError(a_List);
finally
a_List.Free;
end;
end;
end;
initialization
Lock := TCriticalSection.Create;
Include(JclStackTrackingOptions, stTraceAllExceptions);
Include(JclStackTrackingOptions, stRawMode);
// Initialize Exception tracking
JclStartExceptionTracking;
JclAddExceptNotifier(HookGlobalException, npFirstChain);
JclHookExceptions;
finalization
JclUnhookExceptions;
JclStopExceptionTracking;
Lock.Free;