I am running

Build collection.
I get the following error message:

"An error has accrued which will prevent the collection being previewed"
I click the

OK
The indexing continues

140 documents were considered for processing:

    123 documents were processed and included in the collection.

    15 were unrecognised.

    2 were rejected.

************** Build  Started **************

Compressing text...

Creating an index based on text,Source,allfields,metadata,dc.Title,dc.Creator,dc.Subject,dc.Publisher,dc.Date,dc.Type,dc.Format,dc.Language...

Creating information database...

Creating auxiliary files and tidying up...

And then it gets stuck here.
How can I find out what is going wrong?
Noam Kaminer