dxva_sig.txt removal hack

Note: This is a hack for WinXP SP2 Windows Media Player 10 only..

I'm too lazy to write a proper doc for this hack, especially since its waay to simple.. Use diff to spot the difference :)

All the hack does is preventing the dxva_sig.txt file from being created. Quite simple really.

In order for you to use this hack, we must first prevent the Windows File Protection service from working.
WFP is Microsoft's, actually quite good, idea as to how to prevent "critical" system files from erasure/overwriting.
One can now debate whether or not a media codec is a critical file, but according to Microsoft, it is..
WFP works by verifying the digital signature of a "protected file". If the signature fails, the file gets replaced.

Now, since I can't forge a new signature (thank god), WFP will replace the file once we overwrite it.
Fortunately WFP can't just pull the original file out of thin air, why a backup exists inside the windows dir. (Hence the huge size of windows)

So, to use the hack do:

• Config your box to display hidden files, protected files and system files. (Through Explorer => Folder Options => View)
• Ensure your XP distro CD isn't in your box.
• Goto "%systemroot%\system32\dllcache" and erase the wmvdmod.dll file (if it isn't there, then no problem)
• Goto "%systemroot%\RegisteredPackages" and use the search function to search for wmvdmod.dll. Erase any files you find.
  (Alternatively use command console and 'dir /s wmvdmod.dll' from the "%systemroot%\RegisteredPackages" directory)
• Goto "%systemroot%\system32" and delete the wmvdmod.dll file.
• WFP will popup with a dialog saying that it want to restore a protected file, but can't find the XP Distro CD.
• Press cancel, and then yes to the "Confirm that you want to keep the invalid file" dialog.
• Now, copy the hacked version to wmvdmod.dll
  (If WFP pops again, simply do the cancel => no manoeuvre again)
• Start watching a WMV file and see if the dxva_sig.txt file appears.. it should not.. if it does, email me.

A few notes to remember

• Always remember to do a backup before replacing files.
• If you're experiencing problems, it may be because of versioning trouble.. Right-click => properties on wmvdmod.dll and check the version, then the signature. The hacked version's signature is Invalid.
• Try updating your box to the latest windowsupdate, including mediaplayer10 and such stuff..

Below you find the file. As you can see there is more than one. Use the wmvdmod.<version>.hack which matches your wmvdmod.dll version.

 Name                                Last modified      Size  Description
 Parent Directory                                         -   
 wmvdmod.dll.10.0.0.3646.hack        15-Aug-2005 00:34  851K  
 wmvdmod.dll.10.0.0.3646.ms_original 15-Aug-2005 00:34  851K  
 wmvdmod.dll.10.0.0.3650.hack        11-Oct-2004 11:20  848K  
 wmvdmod.dll.10.0.0.3650.ms_original 11-Oct-2004 11:20  848K  
 wmvdmod.dll.10.0.0.3700.hack        24-Mar-2005 17:26  802K  
 wmvdmod.dll.10.0.0.3700.ms_original 24-Mar-2005 17:26  802K  
 wmvdmod.dll.10.0.0.3802.hack        15-Aug-2005 00:34  875K  
 wmvdmod.dll.10.0.0.3802.ms_original 15-Aug-2005 00:34  875K  

If you forgot to make a backup and you want to revert to Microsofts original files, go to Media Player Download and download and install the latest version of the player.