Hosting issues

whenever I try to host create a match for me and my friend on gmod 9, I always get a engine error saying its unable to load authentication library, and nothing and same thing happens to my friend… I know that I can play this online cause I see other servers on there but I still can’t join… can anyone help?

Get gmod10. Gmod 9 is no longer supported by garry. Other users might be more helpful though.

ok can anyone else plz help, how do i see people playing then