Docker Compose Mac Error: Cannot start service zoo1: Mounts denied:

TL;DR: If you're on Docker Desktop 3.0.0, upgrade to 3.0.1 and you should be good.

I also had this problem after updating to Docker Desktop 3.0.0 for Mac. @drewsign's answer solved the problem for me, then I found the following resources explaining there was a bug in 3.0.0 -> so I upgraded to 3.0.1 and problem fixed!

Github issue here

Docker release notes for v3.0.1 here

To force your Docker Desktop app to update (on Mac), click the Whale Icon on the top toolbar, then "Check for Updates". After the update has installed, restart Docker. Now you should need to turn off "Experimental Features -> Use gRPC FUSE for file sharing"

UPDATE 2020-12-14:

This issue appears to be resolved in Docker Desktop 3.0.1 for Mac. If you disabled gRPC, you will likely want to enable it again after updating to 3.0.1.

Previous Answer:

I had this problem after updating to Docker Desktop 3.0.0 (for Mac). After going into Preferences and disabling Experimental Features -> Use gRPC FUSE for file sharing I was able to use volume mounts again.