Whenever I type in the Library Find box I get this message

When I cancel the input (hit X) the message disappears.
3513.Logos.zip
EDIT: here is the Indexer log associated with the above log.
5611.LogosIndexer.log
LibraryCatalogIndex Library catalog indexing canceled; deleting temporary files. ---> not attempted since.

UPDATE:
I deleted the eru4 files with no success and deleted the Index files with no success (the Indexer failed to rebuild it).
After restoring the Index files, I changed the rating of a resource and Logos 5 (not the Indexer) finally rebuilt the index:-
LibraryCatalogIndex Rebuilding library catalog index.
LibraryCatalogIndex (Timed) Attempting to replace index 'E:\Logos4\Data\pmhb2cwb.41l\LibraryCatalog/catalog' with new index 'E:\Logos4\Data\pmhb2cwb.41l\LibraryCatalog/scqlghqy.p0u'.
FileSystemIndexInfo Replacing E:\Logos4\Data\pmhb2cwb.41l\LibraryCatalog/catalog with E:\Logos4\Data\pmhb2cwb.41l\LibraryCatalog/scqlghqy.p0u
LibraryCatalogIndex (12ms) Attempting to replace index 'E:\Logos4\Data\pmhb2cwb.41l\LibraryCatalog/catalog' with new index 'E:\Logos4\Data\pmhb2cwb.41l\LibraryCatalog/scqlghqy.p0u'.
LibraryCatalogIndex Library catalog indexing completed; firing event.