Apple explains how to fix an issue with Security Update 2017-001 on the Mac
Apple has released a support document to help you deal with the issue. If you experience issues with authenticating or connecting to file shares on your Mac after you install Security Update 2017-001 for macOS High Sierra 10.13.1, follow these steps to repair file sharing:
° Open the Terminal app, which is in the Utilities folder of your Applications folder.
° Type sudo /usr/libexec/configureLocalKDC and press Return.
° Enter your administrator password and press Return.
° Quit the Terminal app.
