Curiosity?
To ID the actress in the Steppin’ Out video; it’s right there in the thread title. Did you not see that? 
Agreed. You’re fine, Bo. Keep on detectin’…
*Enquiring *minds want to know. 
Just one of those things people look at out of curiosity, then decide not to give up the harder it seems! Nothing but detective work. Some of us love research and puzzles, nothing creepy to me.
I have no idea why I am so interested, other than it’s turned into a very hard mystery and love research! I also love the song and video, have ever since the good days of watching MTV in the 80s. Be nice to connect a name to the face. North Rockland High School only has yearbooks on Classmates from 1973/74. I’ll ask some friends up in NY.
A poster in Quora said the definitive answer is British actress Clare Holman but I didn’t see it anywhere in her history
Some quick research shows that according to Wikipedia & IMDB, Clare Holman did not begin her acting career until 1988. Steppin’ Out, both the song and the video were released in 1982.
While it is possible this was an uncredited gig, I admit I’m having a hard time believing that it would be necessary/advisable/likely to hire a 17- or 18-year-old (Clare Holmes was born in 1964) in the UK, fly her to NYC to shoot the video, then fly her back; it’s not like it would have been difficult to find someone in NYC to do the gig.
Also, she is and has been in the public eye continuously since 1988. She is a huge star in the UK, having starred in a popular TV series (Lewis) for 9 seasons, amongst other TV, film and stage endeavors. Yet not once has she shared the information that she began her career in a music video for Joe Jackson.
I’m going to to classify this answer as “dubious”, since all available evidence fails to support it.
Absolutely no way that’s an 18 year old. Try again, arrogant quora person.
Someone with Facebook can probably get the straight dope:
I’ll post the response when I get one, eh. Thanks for the link, Blank Slate.
I hate to repeat an earlier prediction, but Cynthia Rhodes was a dancer in two 1982 videos. One of them (Rosanna) was directed by the same guy who directed Steppin’ Out.
I looked at Clare Holman photos and she doesn’t look anything like her to me. The Quora commenter called the high school person’s comment a red herring but that person had links to two commercials that are 100% her.
That Canon commercial is absolutely her, even getting a flower in the commercial like she did in the video with same expression, same face, same woman.
I’m ready to email Canon to see what records they have! Probably none…
I did try newspapers.com with my subscription and tried every kind of search. By high school, name of video, date ranges, and no luck.
There was a Jeanne Cole who graduated from that school in '71 but after finding her wedding photo in a newspaper I saw it was totally, absolutely not Mystery Lady.
I did email Canon. No one there knew anything about the nearly 40 year old ad and they had no records. Most likely it was something an ad agency did for Cannon, with very little input or control from the client company.
I was unable to find which ad agency might have produced it tho I did google for “new york city advertising contract agency cannon 1980” (and 1978 and 1979, 1981, etc.) (or close to that, anyway) hoping to find a news story about an agency securing a lucrative contract.
I’m usually pretty quick to pick up on the creepy vibe and for me, this thread doesn’t have any of it. The woman is almost incidental to the mystery. “There’s information that ISN’T readily available on the internet! WE MUST FIND IT!” 
I love this song, too. Back to lurking.
Nothing creepy about identifying people for the hunt of it!
I emailed Canon before I saw someone else here did, they replied asking me who I worked for and that sort, I answered that I was just trying to identify an actress that I’d seen in that commercial and other ads and a video because she looked familiar. Have not heard back. But if they have no records that’s that.
Wonder if that cereal company has records?
I do have to laugh wondering what that woman would think if people are trying to ID her! I’m sure she did other things, she was rather distinctive looking.
I just discovered this thread and it was like a detective thriller in five-ish pages. I’m quite satisfied that Canon Typewriter Lady is the woman in question, whether we/you manage to find her name or not.
You want creepy? It took the combined efforts of me and four other people to track down a couple of missing classmates for a reunion. These two people definitely had not put themselves out on the internet to be found, but I’m delighted to say we tracked them both down without having to use any paid service. (We also surprised several people who happened to have the same names.)
What was our endgame? To invite them to a reunion.
What if they don’t want to come? We’ll miss them.
What was in it for me personally? The thrill of the hunt. I’m a catch and release kind of guy.
Catch and release, that’s a perfect definition of it!
No reply back from Canon but someone here said they have no records. Maybe the cereal company?
The more roadblocks I hit the more determined I feel, the love of the hunt!
Did anyone try Joe Jackson himself?