Missing Back, Forward and other buttons from Internet Explorer

Please follow the below steps:

1) Launch Internet Explorer,
2) Right click on the toolbar, (toolbar is located on top of your Windows screen)
3) When you will right click on the toolbar, you will be displayed with options like: Menu bar, Links, Status bar, Google, Lock the Toolbars, Use Large Icons, Customize Command Bar.
4) Select Customize Command Bar option, then select "Add or Remove Commands,
5) After doing this, a box with title "Customize Toolbar" will error displayed,
6) Under "Available toolbar buttons:" select the buttons that you need and the ones that are missing from the toolbar,
7) Click on the buttons as said above and then click on "Add->" button,
8) The selected buttons will be displayed under "Current toolbar buttons:", then finally click on "Close" button.

By following the above steps you can restore the missing buttons.
Article Title: Internet Explorer 7 Support
http://www.microsoft.com/windows/products/winfamily/ie/iefaq.mspx