This issue has been resolved in the latest InDesign version 15.1
Adobe InDesign teamFaks supported this idea ·
An error occurred while saving the commentFaks commented
I had the exact same problem.
I used the Terminal.app to change my folder rights as explained by @Ravi Kiran. Problem, at the step 2 (sudo chmod -R 777 /Users/myUserName/Library/Caches/Adobe\ InDesign) I got this message :
/Users/myUserName/Library/Caches/Adobe InDesign: No such file or directory
I don't know why, but the folder Adobe InDesign was missing in my Caches folder of my Library. Luckily for me, I ask a friend (who has the Creative CC too) to send me his own Adobe InDesign folder (/Users/myFriendUserName/Library/Caches/Adobe InDesign). I copy his folder on my computer at the right place (/Users/myUserName/Library/Caches/) and InDesign CC 2018 worked again!