Found it on my C drive. 4.05gb! Is it safe to delete it?
Yes, but Windows will re-create it.
Not sure what you have, but if you had the w-10 install application, it would have loaded. you can’t get that unless you give MS the OK for it.
The error on the update, are known issues and you can remove them by running the update repair utility.
As to the little MS win10 logo on your taskbar, it should disappear when the free update period expires, assuming you don’t want the new OS...I have one Vista machine that does not like it due to hardware issues...not going to update it but I updated everything else, and they are running just fine.