Winding up of unregistered companies: creditor demand and Tribunal discretion govern insolvency and closure procedures. Winding up of unregistered companies is permitted under the Act except that voluntary winding up is prohibited; grounds include dissolution, cessation of business, carrying on only to wind up, inability to pay debts, or the Tribunal's view that winding up is just and equitable. Inability to pay arises from an unsatisfied creditor demand served on the company, institution of proceedings against a member with notice where the company does not take prescribed steps, execution returned unsatisfied, or other proof to the Tribunal's satisfaction. The term 'unregistered company' excludes certain railway companies and registered companies and otherwise covers partnerships, LLPs and societies exceeding the member threshold.