Admission of Absence From a survey of Answers posted so far, there is an admission that Antichrist is not mentioned as such in Daniel 9! To come up with a person with the characteristics proposed by modern eschatologists, most interpreters jump off into other passages of scripture. Only an Anointed One (Messiah), who is also a Prince, is mentioned. Not any "anti-anointed one."
Bad Dude There is indeed, a bad dude in chapter 8, Antiochus Epiphanes, who lived in the Greek Era. But his time of oppression is listed as 2,300 days. This time frame is different from that given in Chapter 9...which should give a clue that he was a different person. And the Chapter 9 person was prophesied to live 490 year in the future (to Daniel). That is well beyond the Greek dude's era.
The placement of Antiochus in the Greek Era also disqualifies this prophecy as one referring to some Mean Critter way off in the 21st century, or beyond!
John's Antichrist The appeal to an Antichrist mentioned in his letters is not germane to this question about Daniel 9. (1 John 2:18, 2 John 7) The antichrist(s) he referred to were present in his day. His days were after the existence of the Anointed One in Daniel 9, who was to minister (live) in the 70th week 490 years after Daniel. (The Messiah ministered around 27-30 A.D., and not 70-90 A.D. in John's writing time.)
Hostile Prince To deny the Prince as ever being The Anointed One because he seems "hostile" is to ignore the previously recorded times when God Himself expressed anger toward the Israelites...to the point of bringing the fiercest of armies against Israel because of their wickedness...and destroying their Temple and sending them into exile! God led the armies!
So for the Anointed One (Messiah), who is the Prince, to instigate the Destruction of Jerusalem is not unusual. ESPECIALLY when we hear Jesus condemning the Jewish rulers in His time! Read Matthew 23, and recall His parables that made the rulers mad because they knew He was talking about them! And when we hear Him declare their "House desolate."
Even if an interpreter does not admit the Prince to be Jesus, the destruction by the people of the prince planned was to be within the time of the first century, not the End of the World in our future.
Question Destination The results of the excursion into the topic of ANTICHRIST may have been to expose the tendency of expositors to read into verses things that aren't there (eisegesis). Especially to prop up eschatological traditions by using verses that don't really apply. This example of exegesis on Daniel 9 is a classic example...and a wake-up call!