Access Denied whilst publishing a solution
This error can also be given if you have an On Premises deployment of Dynamics CRM and the Service Account running the Async Server does not have permissions to the C:\Program Files\Microsoft Dynamics CRM\CustomizationImport folder.
If you are using a 'least privileges' service account for the Async Service Account, ensure you follow the requirements given at https://technet.microsoft.com/en-us/library/hh699825%28v%3Dcrm.6%29.aspx