Hi

You have not provided enough information  - we need, in addition to the information John CB has asked, the version of Windows you are running and the type of images eg jpg, png, etc - see below.

During the renaming you have removed the file extension - ie the  .jpg  part of the name - assuming they are jpg images.

You need to use Windows Explorer to locate the folder that contained the images, set Windows Explorer to view the filename extensions - if you do not know how to do this without knowing which version of Windows you will have to search the Internet to find how turn this option on in your Windows version.

Once you have done the above you will see that the .jpg (png or whatever the image format is) file extension is missing - you need to add this back see images below

  No file extension

  With file extension

HTH

John EB