- I've run sfc from an elevated command prompt with the /verifyonly parameter and with Windows in safe mode and still get the "Windows Resource Protection could not perform the requested operation" error.
Hi JL3008:
Before we go any further, please confirm that your system clock (Control Panel | Clock, Language and Region | Date and Time) is keeping accurate time (even the incorrect time zone can cause problems with some software updates) and ensure that all your media files and personal data are backed up to removable media just in case there's a serious problem with your Vista SP2 OS.
Have you experienced any other problems with your computer besides Windows Update since March 2016 (e.g., a BSOD or a malware detection by your antivirus)? I think it's time for someone to take a closer look at your Windows system files and recent system errors, and I can recommend a few good free forums where you can post Windows dump files or diagnostic reports collected with more advanced tools like the Farbar Recovery Scan Tool (FRST) and get further assistance from someone with expertise in these areas.
I'd give PA Bear's suggestion to replace your Vista SP2 computer some serious thought, because tracking down the root cause of this problem could take considerable time on your part. It might make more sense to simply re-install Vista SP2 (or find a legal copy of Win 7 and upgrade your OS) if you want to use your current machine until Vista SP2 reaches the end of extended support on 11-Apr-2017.
_______________________________________
Without seeing further diagnostics, my best guess at this point is that you could have a corrupted Windows user profile or Windows Update component or could have somehow corrupted the read/write/edit/delete permissions in some of your Windows registry or folders. You've wiped McAfee and BullGuard off your system, but it's also possible that you still have some third-party software on your system that is interfering with Vista SP2. It looks like your computer was originally built as a gaming system, and I don't know if your ASUSTeK M2N8-VMX motherboard came it's own suite of utilities, but ASUS/Gigabyte applications like EasyTuneEngine that come with certain ASUS chipsets are notorious for causing BSODs and other stability issues - see the ESET support article *Blue Screen Error (BSOD) on Systems with ASUS/Gigabyte Motherboards with Chipsets H87/Z87 and H97/Z97* for one warning about ASUS drivers.
I'd advise that you avoid running MS CheckSUR (SURT) or try to run a file like the MS TechNet Reset Windows Update Tool script to try and repair your Windows Update components until you have further evidence that your problem is associated with a corrupted Windows Update component. I can speak from personal experience that trying to fix a Windows Update error can go from bad to worse very quickly if you try to reset your Windows Update components on a machine with corrupted registry permissions.
32-bit Vista Home Premium SP2 * Firefox v51.0.1 * NIS v22.8.1.14 * MBAM Premium v2.2.1
HP Pavilion dv6835ca, Intel Core2Duo T5550 @ 1.83 GHz, 3 GB RAM, NVIDIA GeForce 8400M GS