Changing Endnotes characters

I am writing a long paper & recently purchased a copy of Word 2010. Most of my paper, however, was written in Word 2007. The 2007 Endnotes I have been using are numbered (1,2,3, etc.). When I transferred the document to Word 2010, I expected that my numerical Endnotes would be continued. Instead, Word 2010 substituted its default characters (i,ii,iii, etc.) and I have been unable to change them back to the numerical characters which I prefer. The Footnote-Endnote box has been no help. How can I change my Endnotes back to the 1, 2, 3 sequence?