While Deploying the Solution in Visual studio we will find this error.
Follow the Steps given below in the Screen Shots.
Go to Start Enter Services, in Run or Search Programs and Files
Find the Particular Share Point 2010 User Code Host,It was in Disabled State.
Double Click Onit
It will shows Like this.
In the Start up Type Change Disabled in to Automatic,than Click Ok.
It was Changed in to Automatic,Right Click and Start..
Now Deploy it Again,It will works Fine...