下载windowsupdateagent-7.6.exe安装解决
到微软官方站寻找相关对应系统版本安装

Stand-alone packages for Windows 7 SP1 and Windows Server 2008 R2 SP1
https://docs.microsoft.com/en-us/troubleshoot/windows-client/deployment/update-windows-update-agent#stand-alone-packages-for-windows-7-sp1-and-windows-server-2008-r2-sp1