mpcmdrun signatureupdate uncc. Looking here I can see extracting a downloaded eby4f1rs92m.cf and copying the files to a shared folder should allow me. The application eby4f1rs92m.cf is situated in the "%ProgramFiles%\Windows Defender\eby4f1rs92m.cf" –signatureupdate. mpcmdrun signatureupdate uncc. eby4f1rs92m.cf loeschgruppe- eby4f1rs92m.cf charlotte. eby4f1rs92m.cf signatureupdate unc charlotte. C:\Program Files\Windows Defender>eby4f1rs92m.cf -SignatureUpdate. Signature update started ERROR: Signature Update failed with. set objShell = createobject("eby4f1rs92m.cf") eby4f1rs92m.cf("""C:\Program Files\ Windows Defender\eby4f1rs92m.cf"" ""-SignatureUpdate"""), 0. The command that you're running is not the command that the tutorial is telling you to run. You're missing the string "UNC" eby4f1rs92m.cf The thing I am.