New
#1
WIndows Defender Definition Update Failure
I'm getting a failure updating Windows Defender Antivirus definition 1.259.218.0 (error 0x800070643, protection definitions update failing with error code -2147023293, "fatal error during installation") through Windows Update and by updating within the protection updates function of Windows Defender. The definitions are stuck at 1.259.156.0, but the installation seems to fail right at the end of the installation process. Windows 10 itself is fully updating. This is a new Microsoft Surface Pro (2017) and the definitions had been updating properly. Any thoughts would be appreciated.
(I've tried all of the Windows Update troubleshooting tools, and everything I've found on the Internet is either old, does not apply, or does not work.)