When was U.N.O established in 1939 or in 1942 or in 1945?

The United Nations Organization (U.N.O.) was established in 1945. It was founded on October 24, 1945, after the conclusion of World War II, with the aim of promoting international cooperation and preventing future conflicts. The earlier dates of 1939 and 1942 are not associated with the establishment of the U.N.