TB3 Doesn't Download Emails

I down loaded and installed the new version of TB Portable over TB2 as instructed. Everything migrated perfectly: address book, accounts, emails, etc. I can send emails - no problem. However, TB3 will not check for new emails. Just to make sure I did it right I did a clean install on another USB stick, then imported my account settings using MoseBackup. Still no email checking. I re-installed TB2, and guess I'll stick with that until the bugs are worked out - even though it doesn't seem anyone else is having a problem. Any answers?