RESHRED ALL TO APPLY NEW DOCUMENT LEVEL PERMISSIONS
If you have added a new document level permissions to a document type with existing documents, like the permissions below, for example:
The new permissions will not work on existing documents and you might see problems when opening them. If you encounter this scenario, you can also use the reshred all documents operation in the Migration Tool by following steps 2-8 in the section Reshred All to Sync with Bulk Edit Tool.