Internet Explorer 8 – How to Disable Tabs

Your problem could be related to your IE addons or also if you have a long restricted sites list (tools -> security -> restricted sites):

Check Microsoft's How to make IE open new tabs faster:

Add-ons are loaded by IE when you open a new browser window or tab. This is usually a quick process, but certain add-ons may cause IE to take a longer time than expected. For example, after installing Skype 4.1, this user (and his father) encountered a slowdown in IE on their computers.

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Examine the performance impact of your add-ons using the Manage Add-ons dialog. Click on Tools - Manage Add-ons, and look at the ‘Load time’ column.

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If you do not want to keep a slow loading add-on around, you can disable it, and it won’t be loaded the next time you open a new window or tab. You can also open Add/Remove Programs and remove IE add-ons that you are not using. This removes the add-on for all users on the computer.

If your problem is not related to your addons, then use this file (from Adding unwanted sites to the Internet Explorer Restricted Zone) to delete all your restricted sites:

http://www.mvps.org/winhelp2002/DelDomains.inf (right-click -> install)

I have IE 8.0.6001.18813 and mine restores both windows and tabs. Try the following:

1. Open two windows of IE8 (one should already be open as you are reading this ).
2. Open multiple tabs on each window using different sites for each tab.
3. Open Task Manager (read the following prior to performing the step)

4. On the Application Tab right-click and end task on one of your IE windows.
   (Make sure you do not click on the close dialog for IE. Just end task again.)

5. This should kill both your IE windows.

6. Reopen IE and you should get the restore session dialog.
7. Click restore and both windows and tabs should be restored.