So  yes,  i  have lost  the  dongle.

I  have  tried  the  universal  receiver  from  the KM636,

also   a logitech unify receiver  but no  luck with  either.

i  cannot  even find the   keyboard/mouse  hardware  on the dell site, so possibly  i  need to  use some sort  of  software   to  join with the logitech receiver?

what do i  actually need as  a  replacement?

thanks