I too, have this train wreck after upgrading to latest Beta early yesterday morning. I have had only minor issues with the previous revs. With this rev, I am experiencing kernal panics every time about 20 sec after booting finishes, and I log into my account. I try to hit the error log send to Apple button before each crash. The error logs points every time to “endpointsecurityd”. So, net net, I am able to replicate this ridiculous issue. I don't even have to log into account to have the reboots happen. About 20 seconds after boot up is completed and account log in screen is presented POOF! reboot. I guess the good news is that it faithfully reboots and gets to log in screen, then repeats itself... but I digress... Interestingly, my Bootcamp with Windows 10 boots very quickly and without issue. I also tried to disable Norton suite just for fun, but their techies said one can only launch it to disable things in normal mode. Which of course is currently impossible. So, they recommended trying to drag to trash in Safe mode. But, this has not solved the issue. I also tried the terminal commands that sqrabs posted, (but terminal wouldn't recognize the initial commands in recovery mode). But since it seems to work for others, I will give it another try. I also tried install via recovery mode. It didn't help. So, I guess we just wait for something from Apple to fix this. I cannot believe that Apple actually tested this before sending it out. AND with all of us sending in our reports and reporting through feedback assistant, has anyone heard anything from Apple? Acknowledgement? works arounds, patch, anything? I have been an Apple die hard since 1984. I have never, ever had a debacle like this one. I have never feared installing betas on my main MAC before, and have not had any major issues, but I got seriously bit this time for sure...

Update: I tried the systemextensionsctl uninstall 9PTGMPNXZ2 com.symantec.mes.systemextension routine mentioned below and it says the extension is gone. But like was pointed out below, it also took me about 4 times before it removed the extension... But rebooting into Normal yields same result: reboot, crash, reboot, repeat. Downloaded and ran the Mac removal tool twice (RemoveNortonMacfiles) from Norton/Symantec website But rebooting into Normal yields same result: reboot, crash, reboot, repeat. error log: panic Process name endpointsecurityd Thank everyone for the process and tips below. If anyone has any other ideas, please let us know. Good luck folks.

Update: After a lost weekend in hell with this, I had come to terms with starting over with Catalina if there was no patch this morning. But then I saw bbaale's comment about the reset (systemextensionsctl reset). Last ditch effort to try this.... And it worked!!! I have rebooted it multiple times, and left it running for the last few hours & no crash and reboot. So, the processes offered below did not work for me until the addition of the reset command. Thanks community for all of your ideas. Special thanks to bbaale,RM9981, Bullwyf, & Sqrabs. Cheers!