Try clearing your cache.
If you're using the client, click on "Error!" at the top and select "Delete obsolete files and clear IE Cache"
Cross Knight,
I am having similar issues, but it only seems to work on one of my many browsers.
When using GOOGLE Chrome, I get the same problem as many have posted (even after clearing cache)
But when I use Mozilla Firefox, I don't have the shop issue
As a side note, when using Firefox, I am unable to view the entire page of my PostBox, so that it makes it impossible to reply/take items (But this problem is not in Google Chrome)
So I guess it is select browser problems and/or flash problems, as I know Adobe flash player is having issues working with 64-bit computers/browsers.