In the Name of Allah, the Most Gracious, the Most Merciful.
All praise and thanks are due to Allah, and may the peace and blessings of Allah be upon His Messenger.
Elaborating more on this, Dr. Husam al-Din Ibn Musa `Afana, professor of Principles of Islamic Jurisprudence at Al-Quds University, Palestine, states:
Almighty Allah says: (And eat not up your property among yourselves in vanity, nor seek by it to gain the hearing of the judges that ye may knowingly devour a portion of the property of others wrongfully. ) (Al-Baqarah 2: 188) Almighty Allah also says: (O ye who believe! Fulfill your undertakings…) (Al-Ma’idah 5: 1) In addition, Abu Hurayrah (may Allah be pleased with him) narrated that the Messenger of Allah (peace and blessings be upon him) said: "The claimants would get their claims on the Day of Judgment so justly that the hornless sheep would get its claim from the horned sheep." Abu Hurayrah also narrated: "Whoever takes the money of the people with the intention of repaying it, Allah will repay it on his behalf, and whoever takes it in order to spoil it, then Allah will spoil him." (Al-Bukhari)
Moreover, Abu Hurayrah narrated: "The Messenger of Allah (peace and blessings be upon him) said, 'Do you know who the insolvent is? They (the Companions) said, 'An insolvent man amongst us is one who has neither dirham (a unit of money) with him nor wealth.' He (the Prophet) said, 'The insolvent of my nation would be the one who would come on the Day of Judgment with prayers and fasts and Zakah (alms) but (he would find himself bankrupt on that Day as he would have exhausted his funds of virtues since) he hurled abuses upon others, spoke slander against others, unlawfully consumed the wealth of others, shed the blood of others and beat others. Thus, every one of them would be given of his virtues (i.e., his virtues would be credited to the account of those who suffered at his hands). And if his good deeds fall short to clear the account, then their sins would be given to his account and he would be thrown into the Hell-Fire'." (Muslim) There are many other hadiths indicating that the Muslim should return the rights he had usurped to their rightful owners.
Furthermore, Muslim scholars confirm that whoever wants to perform Hajj should first absolve himself of the rights of others by returning them to their rightful owners. Imam An-Nawawi said: "If a Muslim makes up his mind to travel to perform Hajj or to fight in the Cause of Allah or the like, he should first repent from all sins and evil deeds, return any usurped rights to their owners, settle as many debts as he can, return trusts to their owners, settle whatever dealings or partnership he has with others, write his will and have it witnessed, depute someone to settle the debts he could not settle, and leave his family and whomever he supports sufficient money until he comes back." (See Al-Majmu` Vol. 4, P. 385)
On the other hand, in his response to a similar question, Sheikh Abdul-`Aziz ibn Baz, the late Mufti of Saudi Arabia stated:
If a Muslim determines to travel to perform Hajj or `Umrah (Lesser Pilgrimage), it is desirable for him to advise his family and friends to fear Almighty Allah by observing His ordinances and avoiding all that He has forbidden. He should also write down what others owe him and what he owes others and have this witnessed. In addition, he should hurry to sincerely repent from all sins, as Almighty Allah says: (… And turn unto Allah together, O believers, in order that ye may succeed. ) (An-Nur 24:31) True repentance is represented in giving up the sins, regretting having done them and being determined never to commit them again. A fourth condition is that if the concerned person owes people any usurped rights, related to soul, property, or honor, he should settle them or seek their forgiveness before he travels. This is because it is authentically narrated that the Prophet (peace and blessings be upon him) said: 'Whoever owes his (Muslim) brother a usurped right of property or honor should settle it today, before a Day on which a dinar or a dirham (units of money) will be of no avail. (On that Day, to clear his account) if he has virtues, they will be given to the other (i.e., the creditor) and if he has not, sins of the other will be taken and added to his account'."
Accordingly, one should first settle any rights he has usurped before setting out for Hajj.
Allah Almighty knows best.