Error 1 Error occurred in deployment step 'Activate Features': Cannot start service SPUserCodeV4 on computer 'SERVERNAME' 0 0 SP2010Dev1
The error can be easily resolved by starting the Microsoft SharePoint Foundation Sandboxed Code Service which can be accessed through the Central Administration site in SharePoint. Open the Central Administration site and go to System Settings and click on Manage Service on server:

свернуть