Short of a warp drive-tier break through that causes it to rain Nobel Peace Prizes, not for a while. To be sure, I'm positive we'll have dabbled in interplanetary colonization, or started seriously planning it within our life times, but interstellar will take longer. Space travel, however, remains a necessity for us to survive, so we better get cracking.

Who said I cannot do it?

Interstellar travel is almost certainly thousands of years away from our current technological state. We need to get some better understanding of quantum physics and quantum [i]engineering[/i] before we'd be able to bring the concept of traveling to another star within a reasonable amount of time a feasibility. Colonization of the Solar System, though, I'd assume may begin a little bit before the start of the next millenium.

Year 4000, at the earliest. Certainly not in this millennium.