Security Intelligence Update for Microsoft Defender (KB915597) The update identified as standard delivery mechanism for Security Intelligence Updates
Sometimes KB915597 fails to install with errors like 0x80070643 or 0x80240016 . Here is why that happens with definition updates:
Update Security Intelligence Definition Version | Windows | NinjaOne
Enter the following command: "%ProgramFiles%\Windows Defender\MpCmdRun.exe" -SignatureUpdate . Troubleshooting Common Issues KB915597 - Update for Windows Defender not installing.
The versioning of Windows Defender definition updates can sometimes seem confusing. In the context of the update KB915597, "definition 155" and "11190" refer to specific versions of the definition updates.