Does the installer for 6.13 require a computer restart? I don’t recall a restart being needed in the past.
That doesn’t seem right. Are you sure you don’t have some leftover Rhino process still running. Could be some image or text editor that has opened a file inside Rhino directory. Or even WinExplorer (if you’re using windows) that has some Rhino folder opened.
That’s my guess - there may have been a Rhino that did not close.
Version 6 SR13 (6.13.19031.5531, 1/31/2019) is currently running okay after today’s update without restarting the computer. Not sure what happened but probably not worth pursuing.