C.R.S. § 15-12-401

(1) A formal testacy proceeding is litigation to determine whether a decedent left a valid will. A formal testacy proceeding may be commenced by an interested person filing a petition as described in section 15-12-402 (1) in which he requests that the court, after notice and hearing, enter an order probating a will, or a petition to set aside an informal probate of a will or to prevent informal probate of a will which is the subject of a pending application, or a petition in accordance with section 15-12-402 (4) for an order that the decedent died intestate. (2) A petition may seek formal probate of a will without regard to whether the same or a conflicting will has been informally probated. A formal testacy proceeding may, but need not, involve a request for appointment of a personal representative. (3) During the pendency of a formal testacy proceeding, the registrar shall not act upon any application for informal probate of any will of the decedent or any application for informal appointment of a personal representative of the decedent. (4) Unless a petition in a formal testacy proceeding also requests confirmation of the previous informal appointment, a previously appointed personal representative, after receipt of notice of the commencement of a formal probate proceeding, must refrain from exercising his power to make any further distribution of the estate during the pendency of the formal proceeding. A petitioner who seeks the appointment of a different personal representative in a formal proceeding also may request an order restraining the acting personal representative from exercising any of the powers of his office and requesting the appointment of a special administrator. In the absence of a request, or if the request is denied, the commencement of a formal proceeding has no effect on the powers and duties of a previously appointed personal representative other than those relating to distribution.