there are instructions inside the phpbb3 download, there are instructions here in the phpbb3 section.
basically, you upload phpbb3 just like you would phpbb2, then, go to the install page and fill out forms and click buttons.
it automatically converts your data from your phpbb2 database to the new phpbb3 database ( you do have to create a new database for it ).
phpbb3 does not use any of the phpbb2 files at all, so, you will lose any MODs you have installed.
CH is no longer needed , phpbb3 has sub forums.
you will NOT lose any posts, or members, etc.
I'm baaaaaccckkkk. still doing work on donation basis. PM your needs.
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