Don't want to porvide stronger encryption or security~
 

Hello! I am using Excel 2007, my coworker is using an older version. We
share the same workbook. 2007 keeps asking me, "do you want to increase
security of this document by converting to an Office Open XML format?" I
don't want to be prompted for this ever because sometimes I accidentally say
yes. Its annoying and wastes time, if I want to increase security I would do
it somewhere else before trying to close the document. Can you help me turn
that prompt off?