Partly recover

I'm not too clued up on the I.T side of things...but here goes. I did a recover of 2 excel documents and the messages showed total recover 2 files, fully recover 0 files and partly recover 2 files. When i try to open the documents error message appears that the file format or file extension is not valid. I unticked hide extensions for known file types but still no luck to open/view document.