Hungarian-born of German descent, Winkler began her career as personal secretary of Harry Warner, one of the founders of Warner Brothers. Through most of the silent era, Warner Brothers was strictly a film distributor, and Harry Warner was the man who made the deals. In 1917, Warner Brothers began distributing cartoons of Mutt and Jeff in New York and New Jersey. Warner was impressed with Winkler's talents, and when Max and Dave Fleischer, owners of Fleischer Studios, came to him with their series Out of the Inkwell, he gave it to Winkler and encouraged her to form her own distribution company, Winkler Productions, on a state's rights basis.