If you are seeing this occur with your customers’ files, it may be they are experiencing the one-time conversion to Unicode and the update of the file structures. All documents created prior to version 7 must have the content converted to Unicode. All document structures must be updated to the new file format (where there are more structures to update due to the consolidation of East Asian products). There are also some additional checks that are made to detect document corruption, especially when opening documents created in versions of QuarkXPress prior to version 6.