Synonyms of unsuccessfully

2 Syllables
vainly, feebly, meanly, badly
3 Syllables
fruitlessly, faultily, ineptly, shabbily, crudely
4 Syllables
inexpertly, futilely, disastrously, erroneously, lamentably, imperfectly, blunderingly, maladroitly, unskillfully, inferiorly
5 Syllables
abominably, defectively, incompetently, insufficiently
6 Syllables
unfortunately, inadequately