User.Identity is always null

[kpao]

I have used form authentication in my web application. This works in my local pc. When I put it to my server. Then try logging in using I.E. 6. The server cannot not return the user identity. I tried logging in again. But this time, I use firefox. The server can return the user identity. That's strage.
Is there anybody meet this issue?

 

[kpao]

I found the problem already. What cause this problem is the server name. The name of my server contains "_" character. IIS may not handle this case. So, if anyone who has ever met the similiar issue, please pay attention on your server name.