Trying again.
I have a MacBook that I bought a few weeks ago, and am new to Macs. I was emailed some 30 gif files, they are of stylized maps from a play-by-mail game. I have other maps like these in jpg and pdf files and have no problem opening and viewing them. The gif files open in a small window with a dot in the middle that using the + sign I can enlarge to see that it is just a few blue and white stripes.
I have tried to rename some of the gif files as jpg or pdf and using preview to view, but they can't be viewed like that either. I get the message that the file can't be opened and I should check if its corrupt. I've also tried shortening the name of the files from bg_blue_left-1.gif to something shorter in case the name was too long for this or indeed another format. Still no luck.