Sunday, October 15, 2006

QA - problems running WScript.Shell on 64bit Windows

Question:

Hi,

I'm having trouble running a bat file from an ASP page. It works fine on Windows 2003 Std x32 server but fails now we have upgraded to the x64 edition

In the ASP we are trying to run the following


Set oWSH= Server.CreateObject("WScript.Shell")

errmsg = oWSH.Run("d:\\scripts\\copyiissettings.bat 10.0.0.156",0,True)

set oWSH = nothing

The errmsg is returning 1 (not very helpful)

In the BAT file we are running the following command: cscript.exe c:\windows\System32\iiscnfg.vbs /copy /ts %1 /tu machineusername /tp machinepassword

I am sure the permissions are setup correctly in IIS as both the Application Pool and Authenticated Anonymous User are set as the Administrator. We are also running IIS with he following flag enabled Enable32BitAppOnWin64=True

I can only think maybe there is a problem being related to the fact we are running x64 and perhaps there is a registry setting or group policy setting i need to change?

Thanks,


i figured it out.

problem is that when you call the bat from the ASP it runs as a 32 bit process and runs the cscript.exe from the SYSWOW64 directory and this fails. i copied the cscript.exe from the System32 into the SYSWOW64 directory and this fixed the problem. hopefully this wont cause another problem somewhere else?!

Answer:

Yes, your resulution is one way to address your specific issue, but in general I prefer to modify/manipulate system files only after understanding what is going on and the full ramifications of the change.

Because you configured Enable32bitAppOnWin64=1, WOW64 interactions came into play and complicated matters. Here is what is going on:

  1. When you configure Enable32bitAppOnWin64=1 in IIS6, it makes IIS launch 32bit worker process (w3wp.exe) to handle requests. You see it as w3wp.exe*32 with 64bit Task Manager
  2. The 32bit worker process reads configuration and determines that .ASP is handled by C:\windows\System32\ASP.DLL and attempts to load that DLL
  3. WOW64 subsystem on 64bit Windows triggers when a 32bit process attempt to reach C:\windows\System32 and transparently redirects it to C:\windows\SYSWOW64. So, C:\windows\SYSWOW64\ASP.DLL (32bit DLL installed by IIS6 on 64bit Windows) is loaded by the worker process
  4. 32bit ASP DLL parses the ASP page and looks up ProgId for WScript.Shell in the registry. The Registry also transparently redirects access to Registry by 32bit process to the appropriate Wow6432Node inside the Registry. End result is that the 32bit OCX implementing WScript.Shell eventually gets located and loaded
  5. oWSH.Run( "d:\\scripts\\copyiissettings.bat 10.0.0.156" ) eventually translates into a CreateProcess() Win32 API call made by the 32bit worker process. The .BAT extension is looked up to be processed by C:\windows\System32\CMD.EXE , but will get redirected by WOW64 to C:\windows\SYSWOW64\CMD.EXE (32bit) in the same way as ASP.DLL earlier
  6. 32bit CMD.EXE eventually encounters the CSCRIPT.EXE statement, and after a path lookup and WOW64 redirection, it will run C:\windows\SYSWOW64\CSCRIPT.EXE (32bit) to process c:\windows\System32\iiscnfg.vbs
  7. When 32bit CSCRIPT.EXE tries to load c:\windows\System32\iiscnfg.vbs , WOW64 will redirect it to c:\windows\SYSWOW64\iiscnfg.vbs - which does not exist - and the execution fails with a file-not-found

Based on the above, the following are possible resolutions:

  • Set Enable32BitAppOnWin64=0. This turns off WOW64 everywhere at the source. This may not be possible because you may have legacy web applications which require 32bit. However, if this is the case, I question why you run 64bit Windows at all - running IIS6 in 32bit compatibility mode on 64bit Windows drags in all the WOW64 compatibility cruft without giving much 64bit advantages (the 32bit w3wp.exe still has a 32bit Address Space)
  • Copy 64bit CMD.EXE to %systemroot%\SYSWOW64 . This may not be desirable because legacy applications may depend on 32bit CMD shell behavior
  • Copy 64bit CSCRIPT.EXE to %systemroot%\SYSWOW64 . This may not be desirable because legacy applications may depend on 32bit Windows Scripting behavior
  • Duplicate the IIS Admin .vbs Scripts and IISSCHLP.WSC from %systemroot%\System32 to %systemroot%\SYSWOW64 and use %systemroot%\SYSWOW64\REGSVR32.EXE to register IISCHLP.WSC into the 32bit Registry on 64bit Windows. This creates duplicate .vbs cruft but accomplishes your task without impacting any other part of the system

Good luck

//David

6 comments:

Anonymous said...

i tried the last step you suggested and i get
DllRegisterServerEx in C:\Windows\SysWow64\scrobj.dll failed Return cose was 0x800c0005

Anonymous said...

Instead of duplicating the files, another option is to use FSUTIL to create a hardlink to those files in the other folder. This effectively makes the same single file exist in both folders. Edits to one location are instantly reflected in the other.

Anonymous said...

Good Day! Sang Brown . payday loans

Unknown said...

louis vuitton is roomy for daily essentials. Moreover, lv has flat and phone pockets on the inside and another flat pocket on the outside to add to Louis vuitton bags practicality. Two handles and adjustable shoulder strap enable it to be carried by three ways, in the hand, on the shoulder or across the body. The very versatile louis vuitton handbags makes a harmonious combination with your everyday outfit.

jimmychooshoes said...

Jimmy Choo China strappy sandals
Jimmy Choo Patent leather sandals
Christian Louboutin - Declic leather pumps
Christian Louboutin Very Jaws 140 pumps
Alexander McQueen black skull zipper bootie
mcqueen shoes
alexander mcqueen heels
Alexander McQueen Store
Jimmy Choo sale
Replica jimmy choo shoes
manolo blahnik online store
manolo shoes
manolo blahnik sale
replica christian louboutin shoes
discount christian louboutin shoes
alexander mcqueen shoes
jimmy choo outlet
jimmy choos
jimmy shoes
Manolo Blahnik Shoes
christian shoes

Unknown said...

If you are British, it's so good that there are Yves Saint Laurent uk, YSL shoes, Let me tell you
YSL shoes
Yves Saint Laurent shoes
Cheap YSL shoes
replica YSL shoes
discount YSL shoes
louboutin almeria wedges