Dropping an Index to Speed a Query

Had a complex query - generated by Microstrategy - which was taking over 2000 seconds to come back. Two main tables in the query, Table A had 256000 records and table B over 5million records. The execution plan was not using the index on table A as it should. By implementing an index hint the query time was reduced to 44 seconds.
But being a Microstrategy report, this was not an option.

I examined all the underlying tables and indexes in the query, and all were recently analyzed.

At the end, the problem was solved by dropping the index on Table B, which was based on the prinmary key column of Table A. The query returned in 44 seconds once this index was dropped.