Colo. Rev. Stat. § 15-12-104
No claim may be presented and no proceeding to enforce a claim against the estate of a decedent or his or her successors may be revived or commenced before the appointment of a personal representative, except as permitted by section 15-12-804. After the appointment and until distribution, all proceedings and actions to enforce a claim against the estate are governed by the procedure prescribed by this article. After distribution, a creditor whose claim has not been barred may recover from the distributees as provided in section 15-12-1004 or from a former personal representative individually liable as provided in section 15-12-1005. This section has no application to a proceeding by a secured creditor of the decedent to enforce his or her right to his or her security except as to any deficiency judgment that might be sought therein.
C.R.S. § 15-12-104