It appears you do not have the upgrade files in the main directory.
----/and so on...
but you need to have
--/and so on...
If I go to http://www.nsxprime.com/photopost/upgrades/upgrade.php
I can see the upgrade.php script but it will not run from this directory. It looks like you might have uploaded the entire upgrades directory to the photopost directory causing the upgrade scripts to be in the subdirectory "upgrades". Simply copy all the files from the upgrades folder to the photopost folder and your problem should be solved.