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Wine configuration shows removable media mapped to drives letters as in previous versions of POM. However under Catalina, if you try to access those drives from the Wine command prompt you get 'Access Denied'. Does this problem relate to the new permission introduced for removable media access under Catalina? It looks like there might be some issue with setting up this permission manually - do you need to use a 'helper' from within POM / Wine as per: https://developer.apple.com/forums/thread/124185

If you start playonmac from the terminal command line (e.g. open terminal and type /Applications/PlayOnMac.app/contents/MacOS/playonmac) then it appears PlayOnMac will run under the permissions of 'Terminal' and you will be invited to add the permission to access removable media from terminal.  If you allow this then access will be provided indirectly for PlayOnMac.

It's a workaround but not a solution when starting POM from the OSX GUI.

Thank you! This solved my issues as well!