chrfr said: I confirmed this and filed a bug with Apple on it. With luck it'll get fixed soon. Click to expand...

To be a little more accurate: this breaks File Sharing between High Sierra machines that have the update installed.I can file share to a Mac mini running 10.12.6 (fully updated) just fine. If I try to file share to any High Sierra machine from the Mac mini, credentials are rejected. This is simply an issue with the Security Update. I currently have a fresh install of 10.13.1 going on a test machine to narrow it down to the Security Update 2017-001 for 10.13.1.[doublepost=1511995139][/doublepost]I send an email directly to Craig Federighi. I also tweeted to @AppleSupport and @tim_cook