Delete and reinstall iSeries Access. Make sure the AFP viewer is installed. There are no configuration settings so it must be a corrupted object.
It’s almost certainly not a corrupted object and reinstalling probably won’t help. (It might.)
Most likely the problem is a difference in iSeries Access service packs between different PCs. Download and install the latest service pack for the version of iSeries Access on your PC. If the problem persists, post back for more options.