The 37-year-old Aniston, who played Rachel Green on the popular NBC sitcom, joined Cox as she launched her new FX drama on Saturday with its official world premiere, hellomagazine.com reported.
The new series follows a tabloid editor, played by Cox, and offers the actress a chance to produce a TV offering with her husband David Arquette.
Cox, who was Monica Gellar in "Friends," also offered a hint that she and Aniston are not ignoring the possibility of a cast reunion of the sitcom's cast.
"We talk about a reunion show because we love each other and we hang out all the time," Cox told the Web site. "I'm not opposed to it. Why not? What are we all doing? It sounds fun."