Deleted App Store History

I made the mistake of pressing the x button on my Lion installation on my macbook and now the link in the history saying that it is installed is now missing on all of my computers. How do I get it back?

Lauch the Mac AppStore and select "Account" from the menu on the right side. After entering your password it will take a little moment to load your user profile. Scroll down a bit and one of the menu items will say something about hidden apps as well as an option to few (and manage) hidden apps.

Thank You

I can't believe that was so simple. Thank you so much.

After I wrote what I have below I have now found it, however, it states that I have not installed it. Do you know how to fix this Or does it even matter?

The reason that it happened is because I had updated my macbook with the new lion along with my other three computers, however my macbook, instead of having the icon there and saying it was installed it kept on saying that it was not installed. So I clicked on the icon to install it again and waited for it to download again but then decided that I did not want to risk loosing anything from my macbook as I had not backed it up for a month or so. Thats when I clicked the X and lost the lot. I have not checked what it says on my macbook yet but will take a look when the battery is re-callebrated.

Do you know why it would have said that it was not installed on the macbook when it way. Also do you know what would have happened if I had gone through the entire install again?

Thank you.

David.