I wanted to know that is it ok to pray for the Kuffaar's because as far as I know you can only pray for their guidance but you cannot pray for anything else but someone just recently told me that our Prophet, sallallaahu alayhi wa sallam, did ask Allaah to forgive Kaafir's. If you look at what happened to the people of Kuraish. He did ask for their forgiveness and told God that they don't know what they are doing....so is this true please guide me on this.

All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.

It is permissible to supplicate to Allaah to guide the non-Muslims as the Prophet supplicated to Allaah to guide the tribe of Daws. He said: "O Allaah! Guide the tribe of Daws and bring them forward to me as Muslims." [Al-Bukhari and Muslim] As regards supplicating to Allaah to forgive the non-Muslims, if this is after they died, then it is not permissible according to the consensus of all the Muslims as Allaah Says (what means): {it is not for the Prophet [] and those who have believed to ask forgiveness for the polytheists, even if they were relative, after it has become clear to them that they are companions of Hellfire.}[Quran 9:113]. Moreover, the Prophet said: "I asked Allaah to give me permission to seek forgiveness for my mother and He did not allow me, but I asked Him permission to visit her grave, and he granted my request." [Muslim] Concerning supplicating Allaah to forgive them while they are alive, if the person who supplicates meant supplicating for them even though they died upon disbelief, then this is not permissible; the evidence is in the previous verse. That is because Allaah does not forgive associating partners to Him or disbelieving in Him. Allaah Says (what means): {Indeed, Allaah does not forgive association with him, but He forgives what is less than that for whom He wills, And he who associates others with Allaah has certainly gone far astray.}[Quran 4:116]. However, if he person who supplicates intends supplicating for them if they become Muslims, or wants them to become Muslims, then this is permissible. The evidence on this is that 'Abdullaah Ibn Mas'ood narrated: "It is as if I am looking to the Prophet narrating the story of one of the Prophets whom his people had beaten and injured him in his face. While wiping the blood off his face, he supplicated: "O Allaah! Forgive my people as they do not know. [They don’t know the truth and did not yet believe in you]." Imaam An-Nawawi said: 'This proves the forbearance, patience, tolerance, forgiveness and mercy that they had for their people as they supplicated Allaah to guide them and forgive them.' Allaah Says (what means): {Say to those who have disbelieved [that] if they cease, what has previously occurred will be forgiven for them. But if they return [to hostility], then the precedent of the former [rebellious] peoples has already taken place.}[Quran 8:38]. 

Allaah Knows best