Im trying to upgrade from 5.0-rc16c to 5.0.5. I copied bizroot, bizimage, and syslinux.cfg to flash drive. When I restart it says cannot find kernal...... and just keeps putting up that massage and never starts. copied all the old files back and everything boots and works like it should. I tried copying bizroot, bizimage and the whole syslinux folder onto the flash drive. Now it goes all the way through and just sits there where it use to say tower login and now it just says the syslinux version and just sits there. Any help would be appreciated. I have been running 5.0-rc16c since it came out with out a problem. I am running plex too. 

You should try staring with a fresh flash drive with 5.0.5 and copy over you configs and plugins.  That's what I did, I always like to start fresh when doing a major update and from going from unstable to stable.

I suspect that the boot has been messed up and at the very least it is going to be necessary to run the make_bootable batch file again.

 

As was suggested the easiest way is to back up the files from your current USB stick, and then reformat it and put a fresh release on it.  You can then copy back the config files and key file.  At this point I would suggest all plugins should be omitted.  Once things are up and running you can add back any plugins - ideally making sure you are using versions that are compatible with 5.05.

I was doing some more reading and I think your both right about starting fresh and copying over necessary files, thanks for your help.