What you need :

Place the exif images in the folder C:\temp (this is an example folder, but it can be any folder you choose).
You need to download the utility and place it in the same folder..
You can download the program here : http://www.sentex.net/~mwandel/jhead/jhead.exe.
And you can find the user guide here : http://www.sentex.net/~mwandel/jhead/usage.html.

Start a dos box and navigate to the folder c:\temp (or your chosen folder).
You can convert only one image at the time or all images in the folder at once.
Use this command to convert one image at the time : jhead -de imagename.jpg
To convert all images in the folder at once, use this command : jhead -de *.jpg.

Thanks to Michael Wandel for this excellent and free utility.