I downloaded the Flex 3 trial onto my development box (I'm already a registered Flex 2.10 user).
Compiling my first, simple, Flex application gave me a "Invalid byte 1 of 1-byte UTF-8" error. Mmm ... I was using the default UTF-8 coding and had changed nothing. So ... I downloaded Flex 3 trial onto my laptop and repeated the process. Same error. WTF? Any ideas please guys? I only want to get off the runway with this baby.