Identify Duplicate Lines Items And Generate Report.

I have a report with ~44,000 line items. From this report, I need assistance generating a report that lists all unique line items. I am having problems trying to identify which line items are duplicates as I need to compare 4 different cells in each line to other lines to determine if it is a duplicate item (compare data from columns A, B, E, F)

For example, raw data may be as follows:
Column A………Column B…….Column E…………….....Column F
10/13/2008…….11111111…….71879W561000……….888.88
10/13/2008…….22222222…….239103302000………..222.22
10/13/2008…….11111111…….71879W561000……….888.88
10/13/2008…….33333333…….353496508000………..333.33
10/13/2008…….44444444…….239103302000………..444.44
10/13/2008…….11111111…….71879W561000……….888.88
10/13/2008 ……11111111…….353496508000………..888.88............................

Note from above, there are two occurrences of a duplicate item. As a result, the output table would only list this item once.

I have attached a sample of the spreadsheet with dummy data on one tab and the desired output on another tab. Note that all the data is broken up into blocks of data that is separated by data that is only in the first column of the row.