Windows 7 File Transfer Problem

I was on my desktop today transfering files to a brand new folder on my desktop called GRART245 Project 11. I had three files on the desktop that I wanted to transfer: Interview.docx, resume.docx, and flowchart.vsd. I put transferred them by clicking them all and then hovering over the folder icon and dropping in there. However when I opened the folder only the flowchart.vsd file had transferred. The interview.docx and resume.docx were no where to be found on my computer. I ran a search to confirm it. Fortunately Ctrl Z always comes in handy and undid what i did. This is a small bug that I may have found that will drive people nuts.