I own Adobe Acrobat Pro 9. I purchased a new laptop and installed the program on it, after uninstalling from my prior laptop. Now when I go to use the "combine PDF" feature it no longer works. How can I get this feature to work again?

I own Adobe Acrobat Pro 9. I purchased a new laptop and installed the program on it, after uninstalling from my prior laptop. Now when I go to use the "combine PDF" feature it no longer works. How can I get this feature to work again? Thank you.