There are a lot of 'could be's here. First tell us what op-system and browser you are using, and what happens when you right-click on a picture. If "not recognizing file extensions" means everything is getting saved as bitmap, you may have an overloaded temporary internet file folder. If you are using IE, click TOOLS, Internet options, and use the buttons on the General tab to delete cookies and files. Otherwise, post back with more information.
Ok I did what you did and deleted temp. also I have windows xp , I
E 6 . I saved pics from my son in law this aft. now I am trying to save some pics from Dot Photo I rt click on pic a folder appears I put the dogs ID number in the folder click save and I get no pic when I open my viewer ther is the number but a box and when I try to open it says no application associated with
try this. when you right click an save, an when the box opens up to were you want to save it to. change the file name an the file type. before you click save. that might help. an plus i have found that some web sites wont let you right click an save.