I changed the keboard to Japanese for a letter and when I changed back to American keyboard. the y and z keys changed places. Maybe I selected the wrong keyboard. I have not had this problem before? Al Grappone (89) USN Ret 20" iMac OS X 10.5.8 2. 1 GHz ,PPCG5. 1GB DDFR2 SDram memory, Mail 3.6, iTunes9.2 iLife9 Quicken2007 16.0.0, Epson Perfection 2450 Photo Scanner, Canon iP5200 Photo Printer,Netgear Wireless-N router