Originally Posted by Garan
Filenames that include a "~" will generate the error, "The key contains invalid characters!" from the LotRO client when executing the Turbine.PluginData.Save and Turbine.PluginData.Load methods. To get around that, AltInventory automatically replaces the "~" with an underscore.
AltInventory is the only plugin I've used that includes the character names in the filenames, but good to know.
I haven't actually tried to understand why you did that instead of building one big file with all characters' data in it, but I assume for loading optimization. I didn't bother to do that with KillTracker, even storing everything at the account level, but then I have a lot less data to keep track of than AltInv does.