I recently did a mail merge of names of diners and a brief bio of each person
for a booklet to accompany a dinner, using data from an Excel spreadsheet.  
The first time the mail merge returned about 40 records, just less than half
the number that it should have.  The second time it returned four short of
the required number and the third time I tried there were three records
missing.  I am using Word and Excel 2007.

The next day I used the same spreadsheet to mail merge the names of diners
onto place cards, and it worked perfectly!

Has anyone come across this and is there a solution?  I use mail merge a
huge amount and need to be able to trust that the records returned will be
correct.

Thanks