The "RegisterPlugin" task was not found

Tried to deploy the CRM plugin using visual studio 2010 and this is the error, can someone helP?

Error 1 The "RegisterPlugin" task was not found. Check the following: 1.) The name of the task in the project file is the same as the name of the task class. 2.) The task class is "public" and implements the Microsoft.Build.Framework.ITask interface. 3.) The task is correctly declared with <UsingTask> in the project file, or in the *.tasks files located in the "C:\Windows\Microsoft.NET\Framework\v4.0.30319" directory. C:\Program Files (x86)\MSBuild\Microsoft\CRM\Microsoft.CrmDeveloperTools.12.targets 176 4 CrmPackage1