I literally "cut" the folder/pictures and pasted them onto my little mem stick.
?
As you used Mac and PC, this maybe a compatibility issue. Which version of Mac?
Secondly, here is an error made: you use "cut" instead of copy! This is a dangerous task! I don't use it any more.
It is much more cautious to use COPY/PASTE than CUT/PASTE. It is risky as nobody knows if the system will crash or shutdown before the copying finishes. If so, you will lose files you have cut but not copied yet.
Doing this way, once I lost many important files and folders. Since, I never use cut/paste.
Anyway, this is part of the past now. For the future, my advice is to avoid using "cut". You can copy and delete. It is safer.
Back to your pictures, I think they are still here, as we can see picture previews on your folders. This is good sign!
The question now is, are the overall size of your folders reflect the real image sizes contained in? Right click on a folder and check out the size. If it is bulky and propotionnal to the number of images there, that means the pictures are still readable. If sizes are about ~ Ko, this might mean you lose your pictures!
You said that you cut them onto a flash drive of 5 mb ? This size, 5 mb, seems very low capacity drive. You can't put no more than 5 pictures (1Mo/pic) or 10 pic (500 Ko/image), 15 images maximum with a minimum quality (<300 Ko).
Do you still have the drive and the pictures stored on?
Did you try this:
- Rename your images or folders containing images and try to transfer them.
- Plugin your flash drive back and copy whatever folder to see if you still have the same error message.
- Use any sync program and let it to transfer your pictures between two devices (source>target).
- Disconnect you from the admin account and connect with another account with restricted rights (e.g. guest) and try to copy. You will have, of course, the same error message. Now, shut down the guest account and reconnect with your admin account. Retry to open/copy your pictures and tell us what you got.
Hope this helps.
Good luck