title: Error using WebBrowser control inside PowerBuilder app when select an item in <select> tag
body: <p>I'm using WebBrowser control in a window inside a PowerBuilder 11.5 application. Everything works fine on IE7 and IE8 but the application crashes in IE9 under Windows 7 when you select an item in a  tag.</p>
  
  <p>In IE7 and IE8 I added my application to registry key FEATURE_USE_WINDOWEDSELECTCONTROL. In IE9 under Windows 7 64bits did the same and if the REG_DWORD value that corresponds to my application is 1, the application crashes. If the value is 0, the application does not crashes but item selection with mouse is impossible.</p>
  
  <p>Analyzing errors and dump file, error occurs in the mshtml.dll file with an exception code 0xc0000005, including:</p>
  
  <pre><code>mshtml!CDOMMouseEvent::PrepareEvent
  </code></pre>
  
  <p>Any ideas?.</p>
  
  <p><strong>Update</strong>: My app is a 32bit app developed in Windows XP SP3. </p>
  
  <p><strong>Update 2</strong>: Exception code is 0xC0000005 (I think it's a memory access violation. </p>
  
  <p><strong>Update 3</strong>: Seeking the reason for the error, I've developed an ActiveX control in C# based on the .NET WebBrowser control and I've replaced the Microsoft Web Browser of my PB app with the new one. It also crashes and only in PB, because in a WinForm application (with the same WebBrowser) everything works fine.</p>
  
  <p>Using windbg to analyze dump file:</p>
  
  <pre><code>FAULTING_IP: 
  mshtml!CDOMMouseEvent::PrepareEvent+39
  62b40195 8b39            mov     edi,dword ptr [ecx]
  
  EXCEPTION_RECORD:  00185f70 -- (.exr 0x185f70)
  ExceptionAddress: 62b40195 (mshtml!CDOMMouseEvent::PrepareEvent+0x00000039)
     ExceptionCode: c0000005 (Access violation)
    ExceptionFlags: 00000000
  NumberParameters: 2
     Parameter[0]: 00000000
     Parameter[1]: 00000000
  Attempt to read from address 00000000
  
  PROCESS_NAME:  PB115.EXE    
  ERROR_CODE: (NTSTATUS) 0xc0000005 - La instrucci n en "0x%08lx" hace referencia a la memoria en "0x%08lx". La memoria no se puede "%s".    
  EXCEPTION_CODE: (NTSTATUS) 0xc0000005 - La instrucci n en "0x%08lx" hace referencia a la memoria en "0x%08lx". La memoria no se puede "%s".
  
  EXCEPTION_CODE_STR:  c0000005
  EXCEPTION_PARAMETER1:  00000000
  EXCEPTION_PARAMETER2:  00000000
  READ_ADDRESS:  00000000 
  
  FOLLOWUP_IP: 
  mshtml!CDOMMouseEvent::PrepareEvent+39
  62b40195 8b39            mov     edi,dword ptr [ecx]
  
  WATSON_BKT_PROCVER:  11.5.0.2506
  WATSON_BKT_PROCSTAMP:  489933bc
  WATSON_BKT_MODULE:  mshtml.dll
  WATSON_BKT_MODVER:  9.0.8112.16446
  WATSON_BKT_MODSTAMP:  4fb58407
  WATSON_BKT_MODOFFSET:  230195
  BUILD_VERSION_STRING:  6.1.7601.17514 (win7sp1_rtm.101119-1850)
  </code></pre>
  
  <p>There may be some incompatibility between PB11.5 and Windows 7 64 bit + IE9?.</p>
  
  <p>Thanks in advance.</p>