var moduleCircleFind = VmSolution.Instance["Flow1.Circle Search1"] as IMVSCircleFindModuCs.IMVSCircleFindModuTool;
var moduleImageSource = VmSolution.Instance["Flow1.Image Source1"] as ImageSourceModuleCs.ImageSourceModuleTool;
if (moduleImageSource == null || moduleCircleFind == null)
{

    strMsg = moduleImageSource == null ? "can not find module Flow1.Image Source1" : "can not find module Flow1.Circle Search1";
    listBoxMsg.Items.Add(strMsg);
    listBoxMsg.TopIndex = listBoxMsg.Items.Count - 1;
    return;
}
moduleCircleFind.EnableResultCallback();
moduleImageSource.EnableResultCallback();

vmRenderControl1.ModuleSource = moduleImageSource; //此处报错

c# 最后一句报错，“对路径的访问被拒绝”

vision master 4.3

windows 11

visual studio 2022

项目路径 C:\Program Files\VisionMaster4.3.0\Development\V4.x\Samples\C#\PlatformSDKSampleCS\GetResultControl

运行界面如下图，

但是当运行一下之后，就不报错了。

请问这是什么原因？