If a Document Type contains mapping errors, deleting a document in that Document Type will fail. Deleting the Document Type itself will also fail, because DAT attempts to delete all documents before deleting the Document Type. In order to confirm that this is the problem you are encountering, check the event viewer. The error description will read like this: Error deleting document from DBXL (DocType = '1', DocId = 12) encountered a critical error and needs attention
The user has two options when faced with this situation: fix the mapping or simply disable it. Fixing the mapping is a task that depends solely on the user; follow these steps if you wish to disable mapping:
1. In DAT, click on Edit for the Document Type.
2. In the Database tab, remove the contents of the Connection String field.
3. Click on Save and click OK on the confirmation dialog.
4. In the Documents tab, delete the document(s) you wished to remove.
Of course, disabling the mapping before deleting documents will leave the database in a state inconsistent with the XML documents stored in DBXL, so you will have to manually delete the SQL data as well.