The producers of Saturday Night Live, especially Lorne Michaels, have famously and dramatically banned for life several celebrities from ever appearing on the television show again.
Hosts
Louise Lasser
Louise Lasser was the first SNL host to be banned from hosting again. The ban was due to what was perceived as an incoherent performance and Lasser’s difficulty in working with the cast and crew (Lasser refused to appear in any sketches unless she was by herself or with cast member Chevy Chase).
Charles Grodin
Charles Grodin was banned after he gave a clumsy performance in October 1977. On his one appearance on the show, Grodin missed rehearsal, stumbled his way through the show, and ad-libbed many of his lines.
Frank Zappa
Frank Zappa was banned from hosting the show again because his sense of humor clashed with that of the cast. (His camera mugging and the way he made no attempt to hide the fact he was reading from cue cards were two of the main complaints.)
Milton Berle
This episode was barred from being shown in syndication due to complaints from Lorne Michaels and the cast over Milton Berle. This was due to his habit of upstaging other performers, overacting, mugging for the camera, insertion of “classic” comedy bits and his maudlin performance of “September Song”.
Robert Blake
Robert Blake was banned from hosting after a week of giving writers a hard time, including a fight in which he crumpled up the script of a sketch written by cast member Gary Kroeger and allegedly threw it in Kroeger’s face.
Steven Seagal
Steven Seagal, who hosted on April 20, 1991, was banned from hosting again because of his difficulty in working with the cast and crew. They made note of the occasion almost a year and a half later, as during Nicolas Cage’s monologue on September 26, 1992, Nicolas spoke with Lorne Michaels backstage, saying, “…they probably think I’m the biggest jerk who’s ever been on the show!” to which Lorne replied, “No, no. That would be Steven Seagal.”
Martin Lawrence
The monologue in the syndication reruns is edited to remove Martin Lawrence’s comments about the decline in feminine hygiene, and is replaced with a graphic explaining the comments and how it almost cost everyone at SNL their jobs. Martin Lawrence was consequently banned from appearing on the show again.
Chevy Chase
As an SNL host (as opposed to cast member), Chevy Chase had long had a reputation for being difficult and insulting to the cast and crew, as described in the book, Live From New York: The Uncensored History of Saturday Night Live. In 1985, Chase suggested that a perfect skit for openly gay cast member Terry Sweeney would be one in which he plays an AIDS victim who gets weighed every week. During the week of his 1997 appearance, he offended the staff with lewd comments, and embarrassed Lorne Michaels so badly that he was subsequently banned for life from hosting SNL again.
Adrien Brody
He came out to introduce reggae musician Sean Paul, while wearing Rastafarian attire including faux dreadlocks. Without any prior notice, Brody began rambling in a Jamaican accent for close to 45 seconds before finally introducing the act incorrectly, misannouncing “Sean Paul” as “Sean John.”

Musical guests
Elvis Costello
On December 17, 1977, Elvis Costello and the Attractions performed as a last-minute replacement for the Sex Pistols, who were unable to obtain passports. NBC and the show’s producer Lorne Michaels didn’t want the band to perform “Radio Radio”, since the song protests the state of the media. The band defied them by beginning to play their song “Less Than Zero”, stopping, with Costello telling the audience that there was no reason to do that song, and telling the band to play “Radio Radio” instead. It infuriated Michaels because it put the show off schedule, and the band were barred from performing again.
 

 
Fear

Fear was banned from playing again after the 1981 Halloween episode. With Donald Pleasence as host, the band played that night by request from Fear fan John Belushi, and they proceeded to play offensive songs (“I Don’t Care About You” and “Beef Balogna” among others) and bus in “dancers”. The band also used obscene language and the dancers destroyed the set with their slam dancing onstage. The situation was out of control to the extent that the damage of studio equipment forced Dave Wilson to end the three-song performance by cutting the audio and video to a commercial as they started to play “Let’s Have a War”
Fear’s performance, which only happened on the insistence of John Belushi, took place in front of a group of east coast punks. One of them, Ian MacKaye of Minor Threat and Fugazi, grabbed the mic and screamed “NEW YORK SUCKS!!” several times between songs.
The Replacements
The Replacements were banned from playing on the show again as some of the band members were under the influence of alcohol and lead singer Paul Westerberg yelled “fuck” during dress rehearsal. The band was so inebriated at the time of airing that they didn’t believe they would be able to play.

Sinéad O’Connor
At the end of her second song, “War”, Sinéad O’Connor held up a picture of Pope John Paul II, exclaimed, “Fight the real enemy”, and tore the picture to pieces. Subsequent airings have included the rehearsal taping of the song where Sinéad pulls out a picture of a starving African child before leaving the stage. Host Tim Robbins, who was raised Roman Catholic, did not thank O’Connor during the goodbyes/end credits.
Cypress Hill
During Cypress Hill’s performance on stage, the band members were smoking marijuana on air, and their instruments were destroyed during their second set.
Other
Andy Kaufman
During the November 20, 1982 episode (Drew Barrymore/Squeeze), the audience at home was given the chance to vote on whether or not Andy Kaufman, a regular cameo on SNL, should be banned from the show. The vote was conducted by a 1-900 number. At the end of the night, the people had spoken, and Kaufman was banned from ever performing on SNL again.