Thanks for that,
I think its to do with the size of the picture you upload, using Kes's advice I changed my picture size to 60 pixels high by 90 pixels wide and it seems to be showing now where it wasn't before. If this turns out to the be the problem then to enable all users to see your photo everybody will need to upload a new picture but resized to a thumbnail 60 x 90 pixels, this should prevent the cache issue that is occurring. I would guess the pictures that aren’t showing were uploading in their original size.
I'll double check at home to see if mine is working, if so I'll post a link to an image-resizing programme that should fix the error that some people are receiving, unfortunately it will require most people to submit their pictures again, some pictures such as Viv’s and Kes’s (which I’m guessing were uploaded in the smaller size) are working fine but most are not. I really hate computers.
Joe