unavailable (adj.)

• abortive
• bootless
• fruitless
• impenetrable
• impervious
• inaccessible
• ineffective
• ineffectual
• un-come-at-able
• unaccessible
• unapproachable
• unattainable
• unavailing
• undiscoverable
• unobtainable
• unprocurable
• unproductive
• unreachable
• useless
• vain