[Studio25]

This happens when there's a "hidden" page between the page you're on and the one you want, such as an invisible site tracker.

For example if you go to google and type "accyweb test" your first hit in the list should be the test forum. Click on it to get to the accyweb page, then click "back" or press the backspace key. It doesn't work because google lies to you. If you hover over the link on the search results, it tells you that the link takes you to accringtonweb.com/forum/f91 but it doesn't. Instead you go to googleads.g.doubleclick.net which immediately forwards you to accringtonweb.

When you click "back", all you're doing is going back to that hidden page, and it immediately forwards you to accringtonweb, giving the illusion that "back" doesn't work.