The most common reasons for this happening are:
1) Another program has installed and out of date version of the JPEG library. This is a standard library used by many programs, including Pocket Tunes.
We know of at least two programs that can cause an issue:
As we discover other applications that are not using the up to date library, we will add them here.
2) You are not using the latest version of Pocket Tunes..
In both of the above cases, simply install the latest version of Pocket Tunes from here.
Once the hot sync is complete, open Pocket Tunes before you open any other applications. That should solve the issue.
If the error message returns after that, please contact support, http://www.pocket-tunes.com/scripts/support.php .