Hadith from Saheeh Ibn Habban:
Four types of people will be presented on Judgment Day -- a deaf person, a mentally challenged person, a senile person, and a person who died without hearing the message of Islam. The deaf person will say I was unable to hear the message of Islam. The mentally challenged person will say I was ridiculed by children in the street for my mental deficiency. The senile person will say I could not understand the message of Islam due to being senile. The fourth person will say no one came to me with the message of Islam. Allah سبحانه وتعالى will test these four people. They will be commanded to enter the Hellfire. The Prophet (on him be peace) swore by Allah سبحانه وتعالى that of these four people, whoever enters the Hellfire will find it to have no torment for them.
What we learn from this hadith is that Allah سبحانه وتعالى will accept the excuses of these four kinds of people and he will not punish them with the torment of Hellfire. We are not told what else will transpire in regard to these four people. It is obvious to us that if they pass the final test on Judgment Day, Allah سبحانه وتعالى will give them redemption.
May Allah سبحانه وتعالى make us a means for the spread of His Message to others. We should use all means available to us for this purpose. We should beseech Allah سبحانه وتعالى for the guidance of others. We should pray that everyone is saved from Hellfire and everyone enters Paradise.