Sometimes it can't find the server the photos are on. If you right-click the x box, select properties then see the address. You should be able to copy this and either plug it straight into the address bar or (saving you filling up your address bar with thousands of long addresses) plug it into Google then search. It should come up with a URL which you can click. If the photo is still not there it maybe is because the photo has been removed. Other things that can cause this is your internet cache being too full: in IE go to tools > internet options... and on the first screen delete the temporary internet files.