Chemical activation of the dielectric surface consists in such operations in which catalyst particles are formed on it. Chemical activation allows using different compositions of chemical metallization solutions and obtaining metal coatings on substrates of different nature, different morphology and surface structure. Noble metal compounds and colloidal solutions are mainly used to activate the surface. The former are quite expensive, the latter have low stability during storage due to the spontaneous coagulation process. Palladium-free activation has recently been widely used both for metallization of the surface of unfolded dielectrics and for metallization of through holes of printed circuit boards. Inorganic materials (sitals, polycars, various types of ceramics) and organic fiberglass with an epoxy rubber adhesive layer are used as dielectric material. The purpose of this work is to study the possibility of long-term operation of an activating solution based on copper(I). It is shown that the activating layer obtained during drying in the temperature range 323-373 K consists of CuCl2∙2H2O u Cu2O. The optimal drying mode of the activating solution has been established (T = 353-373 K, τ = 15-20 minutes). The possibility and expediency of carrying out an additional operation - acceleration in solutions of reducing agents is considered. Solutions of hydrazinium chloride (N2H4∙HCl), sodium hypophosphite (NaH2PO4∙H2O), hydroxylammonium chloride (NH2OH∙HCl) were tested as reducing agents, the concentration of which varied in the range (0.1-0.5) mol/l, as well as a solution of alkaline formaldehyde. In order to determine the durability and operability of the activating solution, the stability of the activating solution based on copper(I) was investigated. In this study, additives (sodium hypophosphite in the amount of 0.5 mol/ l and metallic copper with a concentration of 30 g/l) were introduced into the activating solution as a reducing agent, the nature and concentration of which were determined in preliminary experiments. The optimal composition of the activating solution containing (mol/l): copper(I) chloride - 3.10; hydrochloric acid - 3.10; surfactant OP-10 - 0.01; metallic copper 0.47 has been established. Methods of regeneration of the activating solution based on monovalent copper are proposed.