Basic Bible Prophecy

Several weeks ago the comment was made that sin will be present during the 1000 year rain based on the fact that at the end satan will gather a large group to war against God. I get the logic but Daniel 9:24 refers to making an end of sins....and to bring in everlasting rightousness. Is this a diferent period of time then I am thinking? Buy the way I am still unable to bring up the questions as well.