unfastened vs untied

unfastened and untied both are adjectives.

Word	Noun	Adjective	Verb	Adverb
unfastened	No	Yes	No	No
untied	No	Yes	No	No

As adjectives, unfastened and untied are synonyms defined as:

unfastened (adjective)	untied (adjective)
not closed or secured	not tied
not buttoned	with laces not tied
not tied	not bound by shackles and chains
affording unobstructed entrance and exit; not shut or closed