Following are the tips that can be used to make drag function work properly in MS excel.

In 2007 or 2008 version

You have to open excel and click on options > it is beneath the file menu. You can see in this image. Now click on Advanced category, under Editing options.
options excel

Now you have to clear the Enable fill handle ( Follow the images to understand it better) and change the cell drag-and-drop check box to turn on or off.

cell drag-and-drop

In some other versions of excel you can find these options in tools menu  > “Options”.  Now you have to choose “Edit” tab.
Check “Allow cell drag and drop”. Click “OK” to close the dialog box.

 

drag options in excel solution