Error in plugin registration

System.FormatException: Input string was not in a correct format.    at System.Text.StringBuilder.FormatError() +0xf    at System.Text.StringBuilder.AppendFormatHelper(IFormatProvider provider, String format, ParamsArray args) +0x0    at System.String.FormatHelper(IFormatProvider provider, String format, ParamsArray args) +0xe    at System.String.Format(IFormatProvider provider, String format, Object arg0, Object arg1) +0x0    at Microsoft.Crm.ObjectModel.TargetFrameworkVersionValidator.ValidateInternal() +0x4f    at Microsoft.Crm.ObjectModel.PluginValidatorBase.Validate() +0x7b    at Microsoft.Crm.ObjectModel.PluginAssemblyServiceInternal1.ValidateAssemblyMetadata(ExecutionContext context, IBusinessEntity pluginAssembly, CrmPluginAssemblyMetadata assemblyMetadata) +0x30    at Microsoft.Crm.ObjectModel.PluginAssemblyServiceInternal1.VerifyRegistrationAbility(IBusinessEntity pluginAssembly, Boolean createCall, ExecutionContext context, CrmPluginAssemblyMetadata assemblyMetadata) +0x60    at Microsoft.Crm.ObjectModel.PluginAssemblyServiceInternal`1.ValidateOperation(String operationName, IBusinessEntity entity, ExecutionContext context) +0xa7    at Microsoft.Crm.ObjectModel.SdkEntityServiceBase.CreateInternal(IBusinessEntity entity, ExecutionContext context, Boolean verifyAction) +0x3: Microsoft Dynamics CRM has experienced an error. Reference number for administrators or support: #03F5A444

This error happens when our Visual Studio Plugin project was in 4.7.2 while CRM plugin should be in 4.6.2

Change the VS project to 4.6.2 and it should work.