ASP.NET VPN Problem

Hi,

I have 1 application. which is running in intranet(LAN).

But now i need to using the VPN connect to this intranet and using the application.

 My problem is, when i connect the VPN and access the application, some of my page cannot display all the control.

For example, the button will missing.

But some of the pages are ok.

If i try to refresh the problem's page few time. the button may appear. but if i refresh again. it will disappear.

please help.
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