With that callstack, a WAG says its a shell extension causing problems. The things in the callstack is really beyond my knowledge. IDK what an overlay exactly is. Notice its not even a Perl thread, RtlpTpWorkCallback means its a http://msdn.microsoft.com/en-us/library/windows/desktop/ms684957%28v=vs.85%29.aspx thread. "call dword ptr eax+1Ch" says its a C++ vtable call. eax is supposed to be a pointer to a vtable. 0x1C is an offset to a pointer in it. The C++ classes/method names reveal nothing on Google after a couple minutes of searching. Your original post code 
  my $struct = pack "LLLpLLLpLpLppLIppLLpILL",
     (
      88,                        #'lStructSize'       #  DWORD
      $Handle,                   #'hwndOwner'         #  HWND
      0,                         #'hInstance'         #  HINSTANCE
      $lpstrFilter,              #'lpstrFilter'       #  LPCTSTR
      0,
      0,
#     $lpstrCustomFilter,        #'lpstrCustomFilter' #  LPTSTR
#     length $lpstrCustomFilter, #'nMaxCustFilter'    #  DWORD
#I'm not able to make it work with CustomFilter

      $nFilterIndex,                         #'nFilterIndex'      #  D
+WORD
      $lpstrFile,                #'lpstrFile'         #  LPTSTR
      length $lpstrFile,         #'nMaxFile'          #  DWORD
      $lpstrFileTitle,           #'lpstrFileTitle'    #  LPTSTR
      length $lpstrFileTitle,    #'nMaxFileTitle'     #  DWORD
      $lpstrInitialDir,          #'lpstrInitialDir'   #  LPCTSTR
      $lpstrTitle,               #'lpstrTitle'        #  LPCTSTR
      $Flags,                    #'Flags'             #  DWORD
      0,                         #'nFileOffset'       #  WORD
#      0,                         #'nFileExtension'    #  WORD
      $nFileExtension,           #'nFileExtension'    #  WORD
      $lpstrDefExt,              #'lpstrDefExt'       #  LPCTSTR
      0,                         #'lCustData'         #  DWORD
      0,                         #'lpfnHook'          #  LPOFNHOOKPROC
      $lpTemplateName            #'lpTemplateName'    #  LPCTSTR
      , 0, 1
     );

[download]
is wrong. L is always 32 bits. HWND->HANDLE->PVOID->void *, 32 or 64 bit type http://msdn.microsoft.com/en-us/library/windows/desktop/aa383751%28v=vs.85%29.aspx. There are more mistakes in that pack code, including missing alignment holes. I wont cover them right now. Remember void *s and handles dont have to be readable memory addresses to be valid data. They can be offsets into a table. Or encrypted with XOR against a (C static) secret value pointers. They can also be DB primary key GUIDs or something. Win32::API uses Q or L for HANDLE/void *s/char *s/etc. See https://metacpan.org/source/BULKDD/Win32-API-0.77/Type.pm#L160. I found https://metacpan.org/source/JENDA/Win32-FileOp-0.16.02/FileOp.pm#L1217 but that is different from your pack() struct above. Looking through Win32::FileOp, nothing looks 64 bit compatible in it. " $Flags = unpack("L", substr $struct, 52, 4);" that is garbage on Win64.

I tried to contact the module's author to no avail. Also the other addresses mentioned in the perldoc bounce back.

Use RT bug tracker, dont send private emails to CPAN/maintainers authors. Its like asking for tech support in random blog posts. I see nothing I can associate with you at rt://Win32::FileOp.

FileOp never calls CommDlgExtendedError. It is commented out. See http://msdn.microsoft.com/en-us/library/windows/desktop/ms646928%28v=vs.85%29.aspx and https://metacpan.org/source/JENDA/Win32-FileOp-0.16.02/FileOp.pm#L1266. Getting that error code and the bool retval of if ($fun->Call($struct)) { should be your first diagnostic. What is your Windows 8 Perl, 32 bit or x64? You didn't mention what the retval of Win32::FileOp::SaveAsDialog/console output is of your sample script in your OP.

In reply to Re^3: Win32::FileOp issues by bulk88
in thread Win32::FileOp issues by davide_c

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