New forum system, copied posts over. Penalized for Duplicate Content?

Switched to different forum for my cms and converted posts to new forum.

[theChronic]

Hello,
Today I just set up a new more secure forum on my site and had to convert all of the posts over to the new forum. If I leave the other forum there so that old indexes of it can still be reached, will I be penalized for duplicate content? Should I deactivate the old forum to remove the files so they only exist on the new one?

Any ideas would be excellent,
Thanks,
John

[Brett_Tabke]

The dupe content filter generally only penalizes the second page found. Do a 301 from the old pages to the new pages.