I'm not sure if this issue is just happening with me. Last 6 updates give me an error during update and ask me to do a manual update.
Tonight build 1612 gave me same error. Plus when i ran it manually it wasn't able to update pumping out 3 errors regarding the files already exist and did the roll back thing. The roll back deleted an unknown number of files causing the installation to fail. The existing installation also was unable to run.
The 1612 build when run again went through the normal first install thing.
Errors pop up and is failed to read them quick enough and of cause it was unable to replicate.
I haven't come across this during others installs of late so it may be a new under lying issue thats popped up on my system.
Next update i'll punch through it slower for some screenies
Cheers,
Chris