A friend purchased a computer about 2 years ago. The computer had been stolen. He does not know the person who owned the computer.
My friend has changed his life now and has repented for this major sin that he has committed.
Here are the details of how he went about purchasing the computer.
He used totally Halaal money to purchase the computer. He paid 2000 pounds for the computer at that time. So he approached me the other day and informed me that he has repented for this major sin and made a lot of taubah for what he has done and he has changed his life completely.
What he wanted to know from me was that, he is still in possession of this computer and now he wants to sell it. He wanted to know if it is permissible to sell the computer. He was offered 2000 pounds for his computer so before he decides whether to sell it he wants to know whether it can be sold. Also he wanted to know whether he could sell it for the price that he purchased it at or must he sell it for a lesser price. He also wants to know whether he can use the money that he gets after he sells this computer to purchase a Halaal computer. Can you advise him on what to do.?
Make Dua' that Allah puts us and keeps us on the straight path and may Allah give you the ability to answer my question the best that you can. Ameen

Praise be to Allah, the Lord of the Worlds; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

Purchasing stolen items after knowing their reality is forbidden since it is a kind of cooperation in sin and with the thief as well.  Allah Says (interpretation of meaning): {…but do not help one another in sin and transgression. …..}[5:2].

Selling the stolen items is also forbidden since a thief is not their real owner while Shariah approves of selling only what one owns.  Thus, the one who has purchased something from a thief has to return it to its real owner and should take his amount back from the thief.  The Prophet (Sallallahu Alaihi wa Sallam) said: “If a person's belongings are stolen or he loses them, and if he finds the same belongings with a person, the owner is more entitled to take them, and the purchaser has to take his amount back from the seller".  Reported by Imam Ahmad, Sheikh al-Arnawoot considered it as a good Hadith.

Therefore, your friend is not allowed to use the computer and he has to give it back to its real owner if he knows him; otherwise, he has to spend its price in charity.  He can demand its price from its seller,  if he refuses to pay him back the amount he had paid him, he may sue him in an Islamic court or he may forgive him and receive the reward on the Day of Judgement.  May Allah bless you and us.

Allah knows best.