我会首先检查问题发生的时间（或至少是一个窗口），然后考虑改变了什么在该窗口之前可能已触发问题。 IIS服务和Windows服务是否正在运行？

I would first check what time the issue started happening (or at least a window) and then consider what things changed prior to that window that might have triggered an issue. Are IIS services and Windows services running?

此外，您使用的是Internet Explorer吗？使用IE确保它不是浏览器问题。

Also, are you using Internet Explorer? Make sure it isn't a browser issue by using IE.