All righty and old one that I kept forgetting to post nevertheless its a good one. There are a lot of fixes to the “unable to managed metadata service” about granting permissions on web applications, assigning read rights etc. While they might actually solve the problem, it shouldn’t be necessary to grant these right from the beginning. So what is the problem, cause and solution to this from my perspective?
1: Unable to access Termstore Management from a Web Application. (Error Message: Unable to connect to ManagedMetadata Service)
2: Unable to publish ContentTypes, (No Proxy available)
For some reason rights or permissions are broken at some point. Usually during updates. Either Windows Server or SharePoint.
Run the command “psconfig -cmd secureresources”. This will enforce the security permissions set on the different registry keys and folders. Note that this will result in IISreset and should run on all servers in the farm.