The most common types of debt that cannot be discharged are child support; spousal alimony; debt to the government including student loans, tax bills, and penalties; some housing or condo fees; debts owed to someone because of a injury caused by drunk driving or cruel actions; some retirement plan debts; and debts incurred due to divorce.
Creditors may oppose the discharge of some debts during the bankruptcy process, and he must prove that the person or process has been violated to get a supportive ruling for disallowing the discharge. The opposition filing must meet the court's deadlines.
A discharge may be revoked if the trustee or creditor proves that the debtor obtained the discharge under fraudulent circumstances. The court would review the claim and circumstances to determine if there is a justified reason for the revocation of the discharge.
Bankruptcy is a way to start fresh from overwhelming debt, but it is not a method to get rid of all debts.