Depending on what type of assets are in the estate the executor may have to apply for probate.
You might wonder why probate is necessary when the authority of an executor flows from him/her being named in the Will as the estate’s personal representative. The difficulty arises because third parties who have financial dealings with the estate must be sure that the executor is the authorized representative otherwise those third parties may be held responsible for unauthorized distribution of those assets.
Accordingly, many institutions like banks, insurance companies, public corporations and the land registry office that require the executor to have a certificate of appointment of estate trustee with a will (Probate). This document essentially establishes that the testamentary document is the valid last will and testament of the deceased.