I have just deleted a file but it is not shown. Why?

First check it is not in the Recycle Bin. Next, make sure you are looking at the correct drive. Lastly, try refreshing the list by pressing the F5 key (or right-click on the tree and select the Refresh menu item). Sometimes it can take several refresh attempts for a recently deleted file to appear in the list as Windows does not immediately change a drive's contents (changes may be cached in memory).