when I download windows essentials 2012, I get a window showing photo gallery and movie maker, but when I click on it, nothing happens. I receive a message it is already installed on your pc. .

it was installed on my windows 8.1, but somehow it has disappeared.  I went to programs and found it in folder windows live and when I open windows live, another folder with the name photo gallery was there, but nothing is in it. HOW DO I INSTALL PHOTO GALLERY AND MOVIE MAKER AGAIN. OR HOW DO I OPEN IT IF IT IS STILL ON MY WINDOWS 8.1 PC AND WHERE WOULD I FIND IT OR HOW DO I BRING IT BACK