André Krijnen

SharePoint sites using hostnames (HOSTS) with Internet Explorer 8 (IE8) have logon failures

I like to use beta programs. You can see what new functionality will be available before the product is released. But using betas of Internet Explorer is something i have a lot of bad experiences with. Currently we got a report on one of our websites that it had some problems running under Internet Explorer 8. Ofcourse i checked this in my virtual machine by installing the released version of Internet Explorer 6/7/8.

For some reason i was not able to access my SharePoint websites anymore. It kept me asking for my login over and over again. Doing some googling i found out that this issue was also under the beta release and that there is a solution. Keep in mind that this issue is still present in the released version.

It seems that Internet Explorer 8 does a loopback check. This causes SharePoint sites using hostnames (in your HOSTS file) with a logon to have logon failures.I like to use the HOSTS file, because you do not have to use specific port numbers for running your websites. Als for doing demos on events and at customers it looks better.

There are two solutions for the problem. This one i think is the best and less work:

1. Click Start, click Run, type regedit, and then click OK.
2. In Registry Editor, locate and then click the following registry key: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\Lsa
3. Right-click Lsa, point to New, and then click DWORD Value.
4. Type DisableLoopbackCheck, and then press ENTER.
5. Right-click DisableLoopbackCheck, and then click Modify.
6. In the Value data box, type 1, and then click OK.
7. Quit Registry Editor, and then restart your computer. (it seems that this was not needed on my virtual machine).

For more information: http://support.microsoft.com/default.aspx/kb/896861