Merge fails because local changes can not be performed

Plastic keeps trying to find elements to merge and then tells me
‘The merge can not be done because local changes can not be processed. Most likely you don’t have the proper permission to make changes in some of the paths involed. Check the server log for more information.’

What’s happening here? Why don’t I have access and to which files? Where can I access the server log?

Please open a ticket at devops-vcs-support@unity3d.com so we can debug your issue.

Are you using the Unity plugin or the Plastic GUI? What version?

Thanks. I added this to the ticket for my other issue.