If this is occurring printing the organizer, usually we will see a similar issue viewing forms. Based on it being "Error while using" as opposed to "Error while getting" that would indicate a locked file.

Unlocking the file, perhaps on a copy (to retain the original) will get things working. Though - the reason the locked file is producing an error may be addressable by support. Might be good to call in to see what we can do about the locked data, especially if this is occurring for more than one of your locked clients.