unsuccessfully

from WordNet (r) 3.0 (2006)

unsuccessfully
    adv 1: without success; "she tried unsuccessfully to persuade
           him to buy a new car" [ant: {successfully}]

from The Collaborative International Dictionary of English v.0.48

Unsuccessful \Un`suc*cess"ful\, a.
   Not successful; not producing the desired event; not
   fortunate; meeting with, or resulting in, failure; unlucky;
   unhappy. -- {Un`suc*cess"ful*ly}, adv. --
   {Un`suc*cess"ful*ness}, n.
   [1913 Webster]