The way your macro is currently set up, it's trying to copy every file in the Google Drive folder whenever a new file is added to it, which explains why you're getting the "destination already exists" error. If you only want to copy the newly added file, you need to use the %TriggerValue% token, and you don't need the For Each action:
Hi @gglick,
thank you very much for your quick reply.
After replicating your macro, i got this error:
File action failed because source is not a full path (null) in Macro ... while exectuing Copy File "%TriggerValue%".
No problem. I'm guessing you tested the macro by running it from the editor, rather than by actually adding a file? The %TriggerValue% token won't work with a folder trigger unless a file has actually been added to the folder in question, so try adding a test file to the folder and seeing if that doesn't do the trick.