据我所知，它与访问有关.如果您的网站包含不需要访问的模块或页面.您需要首先在aspnet users表中创建一个用户.可能是由于未正确创建此匿名用户而导致空值.

As far as I know it is about access. If your web site has modules or pages that do not need access. You need to create a user first in the aspnet users table. It could be that this anonymous user is not created correctly leading to the null value.

此外，如果要跟踪这些匿名用户，则必须在配置文件提供程序配置中将allowanonymous设置为true.

Additionally if you want to track these anonymous users, you have to set allowanonymous to true in your profile provider configuration.

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