An indication such as you are seeing in the upper left of the screen usually means the boot process is not finding what it needs to complete the boot.
You might check your Bios to confirm the normal boot device is still set as primary. If it is, the system may be having a problem reading the boot files which could mean a errant driver or even drive situation.
One thing you might try is to turn off Fast Startup in Windows. The system boots a little differently depending on whether it is restarting or from a powered down condition.