I found a really good reason why the server sometimes won't accept login connections on startup and it's a trivial mistake. I'm not sure what version introduced it but it was v6+ and therefore my bad. It obviously had serious consequences and because it's a race condition it's more likely on multi-core / faster machines. It's also possible this could explain some cases of the server not accepting logins after startup BUT still allowing logged in users to transfer files (i.e. not the bad lockup bug).
I'm not positive yet, but I think I found a bug in FlashFXP and FTPRush transferring files when uploading via the loopback interface. It's not too big of a deal when using SSL transfers, but it truncates the file when using unencrypted transfers. I couldn't believe BOTH of them wouldn't handle this correctly and so it's still possible it's my fault but ioFTPD to another copy of ioFTPD on the same machine via loopback is perfect... Needless to say a lot of hours were lost trying to track this down and then convincing myself they must be at fault and trying to prove that, but let's face it uploading via the loopback interface which means the same machine just isn't that common of a thing unless testing... It's possible this is a win7 x64 new "feature" but my research says this is allowed behavior by the windows library and a somewhat common programming bug.
Now I can get back trying to figure out the openSSL issues
