It sounds like RTC is having a problem creating your local Eclipse workspace. It looks like you are trying to use a workspace at "/home/username/workspace" but that one already exists at "/home/username". Try pointing the client at a fresh workspace that doesn't conflict with these paths and see if that resolves the problem. If you aren't being prompted for a workspace location when you start the client, then you can create a new one using File > Switch Workspace from within the client.

Hi Ashley - can you look up for existing .jazz5 folders in /home/username/ or higher in that hierarchy?

I think the error message is trying to tell you that you can't create a sandbox inside a sandbox. So it might be that you already have a sandbox above the location you provided that is causing trouble. Let us know if you find a .jazz5 folder in /home/username/ or /home/ .

Then we can discuss a workaround - e.g. delete this .jazz5 folder if you're sure it is no longer needed and user won't lose data from local changes that may not have been checked-in. After that, you should be able to create a sandbox under /home/username/workspace since RTC won't believe there's a sandbox higher up in that path.