Windows Loopback Check prevents accessing website from local server using FQDN

Because of a loopback check functionality in Windows you may find yourself in a situation where you cannot acces a website from the local server using the FQDN. You can access the site remotely using the FQDN or you can access it locally by IP, but you CANNOT access it locally using FQDN.

Even though you can disable the loopback check, the recommended solution is to add the FQDN to the BackConnectionHostNames using regedit:

1. Click Start, click Run, type regedit, and then click OK.

2. Locate and then click the following registry subkey:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa\MSV1_0

3. Right-click MSV1_0, point to
New, and then click Multi-String Value.

4. In the Name column, type
BackConnectionHostNames, and then press ENTER.

5. Right-click BackConnectionHostNames, and then click Modify.

6. In the Value data box, type the CNAME or the DNS alias, that is used for the local shares on the computer, and then click OK.

Note Type each host name on a separate line.
Note If the BackConnectionHostNames registry entry exists as a REG_DWORD type, you have to delete the BackConnectionHostNames registry entry.

7. Exit Registry Editor, and then restart the computer.

Reference: https://support.microsoft.com/en-ca/help/926642/error-message-when-you-try-to-access-a-server-locally-by-using-its-fqd