The issue has been fixed with Apple’s MacOS High Sierra 10.13.4 Beta (17E139).
You can try out the fix by updating your machine to the beta update from Apple.
Let us know if the issue is fixed for you after aforementioned High Sierra beta update.
An error occurred while saving the commentPeggy commented
Upated to 10.13.4 and now InDesign 5.51 won't package fonts. Checked permissions, all ok.
also being asked to authenticate files going on and off hard drive. Checked all permissions.