[Solved] How to Fix Windows could not search for new updates unknown error “Code 8000FFF”

The unknown error with “Code 8000FFF” occurs on Windows 7 when users try to install pending updates through WU or WSUS. Usually, KB3212646 is the update that ends up triggering this error code caused by a bug that Microsoft has patched. Run the Windows Update troubleshooter and apply the recommended fix that may resolve this error or manually install the KB3212646 update downloaded from Windows Update Catalog. Follow the below resolution to eliminate this unknown update error.

Content Summary

Solution 1: Windows Update Troubleshooter
Solution 2: Reset Windows Update Component
Solution 3: Install KB3212646 and KB3177467 Update Manually
Solution 4: Execute SFC and DISM scans

Solution 1: Windows Update Troubleshooter

Step 1: Press Windows key + R to open a Run dialog box.

Step 2: Type control and press Enter to open Control Panel.

Step 3: Type troubleshoot in the search bar, click on the Troubleshooting tab to expand the list of integrated troubleshooters.

Step 4: In the Troubleshoot computer Problem page, click on System and Security.

Step 5: Click on Windows Update under the Windows category.

Step 6: Click on the Advanced button.

Step 7: Check the box associated with Apply repairs automatically. Then click the Next button to proceed.

Step 8: Wait until the initial scan is complete, then click on Apply this fix.

Step 9: Once the process is complete, proceed to restart the computer.

More detail about Windows Update Troubleshooter at Windows Update: FAQ and Fix Windows Update errors.

Solution 2: Reset Windows Update Component

Step 1: Press Windows key + R to open a Run dialog box.

Step 2: Type cmd then press Ctrl + Shift + Enter to open an elevated CMD Prompt. When you’re prompted by the UAC (User Account Control), click Yes to grant admin access.

Step 3: Type the following commands in order and press Enter after each line to stop the Windows Update, MSI Installer, Cryptographic, and BITS services:
net stop wuauserv
net stop cryptSvc
net stop bits
net stop msiserver
ren C:\Windows\SoftwareDistribution SoftwareDistribution.old
ren C:\Windows\System32\catroot2 Catroot2.old
net start wuauserv
net start cryptSvc
net start bits
net start msiserver

Step 4: Try to install the update.

Solution 3: Install KB3212646 and KB3177467 Update Manually

Step 1: Download KB3212646 update from Microsoft Update Catalog. Look for the appropriate driver, CPU architecture and the Windows version that you’re using.

Step 2: Click on the Download button associated with it to start the download.

Step 3: Navigate to the location where you downloaded the KB3212646 Update, right-click on the .inf file and choose Install from the context menu.

Step 4: Follow the on-screen instructions to complete the installation.

Step 5: Restart the computer after installation completed.

Step 6: Download KB3177467 Update from Microsoft Update Catalog then perform Step 3 to Step 5.

Solution 4: Execute SFC and DISM scans

Step 1: Press Windows key + R to open a Run dialog box.

Step 2: Type cmd then press Crl + Shift + Enter to open a Command Prompt with admin privileges. When you are prompted by the UAC (User Account Control), click Yes to grant administrative privileges

Step 3: Type the following commands and press Enter after each one to initiate DISM (Deployment Image Servicing and Management) scan and repair:
Dism.exe /online /cleanup-image /restorehealth
Dism.exe /online /cleanup-image /scanhealth

Step 4: Once the DISM scan and repair is completed, close the elevated CMD window and restart the computer.

Step 5: Perform Step 1 and Step 2 to open an elevated Command Prompt again.

Step 6: Type the following command to initiate SFC (System File Checker) scan:
sfc /scannow

Step 7: After the scan is completed, restart the computer.

More resolution refers to:
Microsoft Comunity > Error Code 8000FFFF when trying to update windows (windows 7 64bit)
Sysnative > KB4471318 update failure- Error Code 8000FFF Windows 7 Pro x64