If you are seeing the following error on your Mac - "Couldn’t communicate with a helper application. Try your operation again. If that fails, quit and relaunch the application and try again."
This signifies your OneDrive app is either not running or has disconnected from the Sharepoint server.
To clear this problem, you will need to do the following: -
Check the OneDrive is running
On the menu bar, at the top of your Mac desktop, there will be a series of icons on the right hand side.
Can you see this one at all? 
It might have a small black circle on the bottom corner.
If you can't see this at all, you will need to go into your Applications folder and run the OneDrive app. After a short while, the icon should appear on the menu bar.
It is there but has a black circle on it
There are two reasons why a black circle will appear on the icon.
- Logged out and disconnected from 365 or
- A synchronisation issue
Click on the icon and if you are asked to sign in, you will need to log back into your 365 account. Your account name will normally be shown to you, if the application has been previously configured. All you will need to do is type the 365 password. If you do not know what it is, contact BCS support and we can check our records or reset the password for you.
Once entered, the app will check you are all up-to-date and then you will be able to carry on working as before.
If there is a synchronisation issue, this will be down to some files not being able to be downloaded or uploaded and the app will provide you with a reason for this and the steps required to allow the file(s) to be synchronised as required.
If you have any problems, please feel free to contact BCS support.
