I've run into this situation more times that I can count: I set up a new web server and no matter what I do, I cannot log into websites on the server that require authentication while I am browsing to them from the console. I used to pull my hair out over this problem until I discovered the problem is in the Windows Local Security Authority (LSA) and it can be easily remedied.
- Open your registry editor by going to Start –> Run and enter regedit and click OK.
- Go to
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa in the registry editor.
- Right-click Lsa, click on New and select DWORD value.
- Enter DisableLoopbackCheck and press Enter.
- Right-click DisableloopbackCheck and select Modify.
- In the Value data box, enter 1 and click OK.
- Reboot your server.
Several years later someone wrote the following KB article that includes this fix with a description of the problem, as well as an alternate workaround: