Hi, I've found similar threads but none solve my problem.
I'm using wordpress with Photocrati theme and have installed the simpleviewer pluging which works perfectly - until I update to the pro version as per the instructions on the support site.
Once I upload the folder in the instructions, overwriting the old version, I simple get:
Here's the page link
I've updated my Java and Flash plugins just to be sure I have latest, and repeated the process twice with the same results.
Using Windows 7, Firefox 4, Photocrati theme (Which I feel must support pro if it supports the free version)
Thanks for your help, and the great viewer, it's long been a favorite of mine and I'm looking forward to getting it working on my wp site.