The problem will continue it's not merely a matter of getting a new forum. The migrating of data across to new forums for the sake of security, is what created our challenges in the first place. Furthermore we cannot allow searches to go all the way back or searches will lock up the forum funtionality for everyone. The real solution would be to remove the data going back more than 3 years entirely. Not too many forums have data going back more than 10 years. These forums started in 2000 and data was migrated in from 1998 back then.
It's also near impossible to manually sort because threads go off topic or there wasn't a proper topic given which means reading the old post manually. Time wise unwieldy. Since they were migrated from one forum to another a search doesn't always pick them up so removing them would be the most logical option.
Someone kindly calculated that I've rewritten the PhotoReading book at least 3 times on the forum. Not to mention stuff for the other forums so don't worry about asking questions that may have been asked before I still find new and cool stuff to share.
If you happen to go mining back the pages of the forum and find good stuff. Make a new post and link it back you might even notice old links are non-functioning because of the migrations. Still share the gems. A clear topic and brief summary paste the link and we will have searches that take us further back

AlexK