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On my new Windows 7 machine (Windows 7 Ultimate 64-bit upgrade from Vista), I find that something with the printer drivers is repeatedly adding settings to the PendingFileRenameOperations key in the registry.

In particular, there are two DELETE entries for:

  • C:\Windows\system32\spool\PRTPROCS\x64\1_ML2550pc.dll
  • C:\Windows\system32\spool\PRTPROCS\x64\1_HPZPPLHN.DLL

I recognize that ML2550pc.dll is for my Samsung ML-2552W printer and HPZPPLHN.DLL is for my HP Deskjet and Laserjet printers. Note that the file that Windows wants to delete is prepended with a "1_". In the C:\windows\system32\spool\PRTPROCS\x64 directory, I do find the 1_ files as well as the originals without the 1_ prepended.

Things I have tried to clear out this setting:

  • I have restarted the computer multiple times.
  • I have removed all HP and Samsung printers from my Devices and Printers.
  • I have manually deleted the files (both the 1_ versions and the other versions).

Nevertheless, after restarting, the DLLs reappear and the 1_ DELETE entries are added to PendingFileRenameOperations. This problem seems to have occurred on two separate installations of Windows 7 upgraded from Windows Vista.

This problem does not seem to occur on my 32-bit clean install of Windows 7 pro. It also does not seem to occur on a 64-bit clean install of Windows 7 Ultimate.

What can I do to correct this issue?

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up vote 0 down vote accepted

After applying some recent Windows Updates that updated the printer drivers, the problem seems to have gone away. I think the problem was with the drivers.

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