How to uninstall PAE Patch for XP?

Discussion in 'Windows XP / Older OS' started by yotoprules, Jul 28, 2023.

  1. yotoprules

    yotoprules MDL Novice

    Jul 28, 2019
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    Hello!
    I tried installing the "WinXP-PAE-Patch" and while it appeared to work, it causes my machine to BSOD with "IRQL_NOT_LESS_OR_EQUAL" after opening a few programs.
    I have run Memtest86+ and it passed 2 passes with 0 errors, plus Windows 10 ran fine, albeit slowly, on this machine.
    The problem I have is, without the PAE patch, Windows XP is only able to use 2.5GB of the 4GB RAM. Whereas the PAE Patch let me use all 3.75GB (as I have allocated 256MB to the X1200 in the BIOS).
    Is there a way of uninstalling this patch? There is no documentation for this and I can't find the supposed backup.
    I did try another PAE patch before this, and that kept causing a black screen instead of a BSOD.
    Thanks!
     
  2. acer-5100

    acer-5100 MDL Guru

    Dec 8, 2018
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    I never had problems with PAE in XP, even on machines with Intel iGPUs that have problems in Vista-W10 x86

    Anyway a good patcher usually duplicates the boot entry to boot with or w/o the PAE patch, just set the option you want as the default one.
     
  3. diderius6

    diderius6 MDL Junior Member

    Mar 8, 2020
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    23
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    Hi,
    you can just change back to the original one ntoskrnl.exe and/or ntkrnlpa.exe in windows\system32
    Dietmar
     
  4. acer-5100

    acer-5100 MDL Guru

    Dec 8, 2018
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    No need to "change" anything, unless the patch was poorly implemented

    All you need is to set the right order (or remove the unwanted option) in boot.ini

    Just like the sample below

    Code:
    [Boot Loader]
    Timeout=5
    default=multi(0)disk(0)rdisk(0)partition(1)\windows
    [Operating Systems]
    multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Windows XP Media Center Edition 2019 PAE"  /fastdetect /pae /noexecute=optin /kernel=ntkrnlpa.exe /hal=halmacpi.dll
    multi(0)disk(0)rdisk(0)partition(1)\WINDOWS="Windows XP Media Center Edition 2019" /noexecute=optin /fastdetect