Sometimes, but not always, when Win10 boots I get an Error message in a small window in the middle of the screen which is usually hidden by other windows generated at start-up. It has a white 'X' on a red dot as an icon and the Title is "Error".
The message is "Unexpected initialization error. If the error reoccurs, please re-install the program".
There is no indication of which program, file or service failed - or indeed, if it is still running but with problems.