Where have you guys been?! This has been a problem (Vista, XP SP2, XP SP3 etc - one good thing about it is that it is not fussy about the OS!) for ages now, can't remember when I first noticed it, but certainly long before most of the versions mentioned here. Yes you can manually re-build it using Run Quick Sys Analysis. Or if you don't trust that to do a thorough job, uninstall and reinstall jv16PT (reinstalling over the top won't fix it). But the best way is to relax for a while. It seems to have some sort of timer built in. Give it 24 hours (I haven't got down to the exact time, but 24 hours does it, so it's that or less) after you've last flushed the cache, flush it again, close, restart and voila, you get the invitation to rebuild. And before someone jumps in, yes I know this is not a fix. At best you could call it a workaround. Whatever, it works.
