Hello;

If you are installing Exchange Server 2007 on Windows Server 2008 and there are some errors due to IPv6 You can follow the steps below to turn off IPv6 completely

Disable IPv6
If you are not using IPv6 in the Exchange environment, we recommend that you disable it.

To disable IPv6

1. In Control Panel, open Network and Sharing Center.
2. In the Tasks list, click Manage network connections.
3. Right-click the connection from which you want to remove IPv6, and then click Properties.
4. Click to clear the Internet Protocol Version 6 (TCP/IPv6) check box, and then click OK.
5. Close Network Connections, and then close Network and Sharing Center.
6 In Windows Explorer, locate the hosts file in the following location:

%windir%System32driversetc
7. In Notepad, open the hosts file.
8. In the hosts file, remove the following entry:

::1 localhost
9. Save and then close the hosts file.
10. Start Registry Editor.
11 . Expand the following subkey:

HKEY_LOCAL_MACHINESystemCurrentControlSetServicesTcpip6Parameters
12. Right-click Parameters, point to New, and then click DWORD (32-bit) Value.
13. Type DisabledComponents, and then press ENTER to name the new value.
14. Right-cl ick DisabledComponents, and then click Modify.
15. In the Value data box, type FFFFFFFF, and then click OK.
16. Exit Registry Editor, and then restart the computer.