A few days ago, without my having made any changes that I know of (possibly an automated Windows 10 update?) when I start my computer I get this screen asking me to select my boot drive.

This is annoying and I would like it to go away, but don't know what to do about it. In any case, is it something I should be worried about?

tanstaafl.

Possibilities, ordered from least likely to most likely:

- Virus did something to your BIOS.
- Computer's BIOS settings got changed so that it prompts you for which boot device you want, instead of automatically selecting a specific one.
- Computer's current set of disk drives got changed so that it no longer knows which device to boot.
- Something is leaning on the computer keyboard or its recovery button, causing the BIOS disk selector screen to appear. (Or the button/key is now faulty.)
- Computer's BIOS got corrupted and now it's back to bog-standard defaults again and needs to be reconfigured from scratch.
- Computer's BIOS is set up so that if there is a removable disk inserted (USB or CD), it will prompt you before booting, just in case you wanted to boot to the removable disk.

Most likely you simply need to go into the BIOS and configure it to always boot to your primary hard disk:

https://learn.g2.com/windows-10-bios

(actually, that screen in your screen shot says "enter setup", so if that gets you into the BIOS settings that might be fine... unless it's a virus...)