Giving Zakah to appropriate recipients

I wish to distribute my Zakah to appropriate recipients, but need help to identify them. How can we know? If we give our Zakah to ineligible persons, will it be accepted?

All perfect praise be to Allah, The Lord of the Worlds. I testify that there is none worthy of worship except Allah, and that Muhammad is His slave and Messenger.

Allah restricted that the zakah be given to eight kinds of people as He says: {As-Sadaqaat (here it means Zakat) are only for the Fuqaraa' (poor), and Al-Masaakin (the poor) and those employed to collect (the funds); and for to attract the hearts of those who have been inclined (towards Islam); and to free the captives; and for those in debt; and for Allah's Cause (i.e. for Mujahidoon - those fighting in the holy wars), and for the wayfarer (a traveller who is cut off from everything); a duty imposed by Allah. And Allah is All-Knower, All-Wise.} [At-Tawbah 9:60]

What is meant by the saying of  Allah "Those who are fighting in Allah's cause", is fighting in the cause of Allah and what all that entails, and what the Mujahid needs, like medicine and medical treatment, and this is only possible in hospitals, like surgical operations. Therefore building hospitals with zakah money to treat the patient of jihad in the path of Allah is permissible, but it is not permissible to spend the money on health institutions that are not limited to treating Mujahideen. It is an obligation on a Muslim to spend zakah on whoever deserves it, and one has to do his best to spend it appropriately.

The author of 'Mawahib Al-Jalil' stated that "it is permissible to give zakah to whoever claims to be poor if there is no evidence proving the contrary. And if he is among the people of the country (locality) then his matter should be disclosed if possible…" If a person does his best and gives the zakah to a person he thinks deserves it but at the end it is concluded that he/she does not deserve it, it is said that this will suffice him. so he does not have to pay the zakah again. However, some scholars believe that if a person pays the Zakah to some one and finds out that such a person was not liable for Zakah, then he has to pay the Zakah again.

Allah knows best.