有人在您的页面上发布了很多表单域.最近的安全更新引入的新默认最大值为 1000.

Somebody posted quite a few form fields to your page. The new default max introduced by the recent security update is 1000.

尝试在 web.config 的 块中添加以下设置.在此块中，您将最大化 MaxHttpCollection 值，这将覆盖 .net Framework 设置的默认值.您可以根据表单需要相应地更改值

Try adding the following setting in your web.config's <appsettings> block. in this block you are maximizing the MaxHttpCollection values this will override the defaults set by .net Framework. you can change the value accordingly as per your form needs

<appSettings>
    <add key="aspnet:MaxHttpCollectionKeys" value="2001" />
 </appSettings>

更多信息请阅读this 帖子.要更深入地了解 microsoft 的安全补丁，您可以阅读这篇知识库文章

For more information please read this post. For more insight into the security patch by microsoft you can read this Knowledge base article