Cannot insert duplicate key row in object 'dbo.umbracoNode' with unique index 'IX_umbracoNodeUniqueID'

After performing a USync import to update some content we are getting the following error when trying to courier a PDF file in our media section:

Server was unable to process request. --->
Error extracting item, ID: 2eba4892-59ff-4b71-b630-1b73c3e061aa_d8e6ad84-e73a-11df-9492-0800200c9a66,
Name: PDF, Type: Umbraco.Courier.ItemProviders.DocumentType ---> could not insert:
[Umbraco.Courier.Persistence.V6.NHibernate.EntityClasses.UmbracoNode
[SQL: INSERT INTO umbracoNode (createDate, level, nodeObjectType, path, sortOrder, text, trashed, uniqueID, nodeUser, parentID) VALUES (?, ?, ?, ?, ?, ?, ?, ?, ?, ?); select SCOPE_IDENTITY()]
---> Cannot insert duplicate key row in object 'dbo.umbracoNode' with unique index 'IX_umbracoNodeUniqueID'. The duplicate key value is (2eba4892-59ff-4b71-b630-1b73c3e061aa).

The 2eba4892-59ff-4b71-b630-1b73c3e061aa is the uniqueID for the PDF in the umbracoNode table and I have cross reference the databases that courier is deploying from and to and this record is identical.

Does anybody know how to resolve this issue?

Many thanks in advance


This is a companion discussion topic for the original entry at https://our.umbraco.com/forum/105221-cannot-insert-duplicate-key-row-in-object-dboumbraconode-with-unique-index-ix_umbraconodeuniqueid