Hiren Solanki wrote:

Follow the procedure click '4' click 'sqrt' click '-'(Minus sign) click '2' Answer should be 0 But It comes back with '-8.1648465955514287168521180122928e-39' answer [Edit] Tested with XP and Seven _[/More Edit] Windows Server 2008 R2 comes same with yet another answer '-1.068281969439142e-19' _[/More Edit] [/Edit]

Windows XP calculator also gives '-8.1648465955514287168521180122928e-39' answer. Long term bug I guess!