I believe it originally came with Windows 7, but I'm not sure about your specific model. As such, I'll guess it may have to do with the driver for either the motherboard or the keyboard itself. Try visiting the Dell website and see if there are updated Windows 10 drivers available for your computer model's keyboard, or even the motherboard/chipset. If so, download and install them. It may even need an updated BIOS. Check for that also. The problem with many Windows 10 upgrades is that they may not get all the hardware drivers correct for each and every system. As users, we need to check to make sure.
Hope this helps.
Grif
Hi,
For the record, I'm not an adult and I'm really bad at computers so I apologize in advance. I have a Dell Inspiron 15 (5000 Series) that runs Windows 10. I was writing something in Google Docs when my keyboard built into my laptop just stopped working. I'm almost certain this isn't a hardware issue. When booting up the laptop, before the OS loads, I can tell the actual hardware of the keyboard works, since the Caps Lock key is responsive. (I have also checked to see if I have filter keys on. I do not.) I'm guessing this has something to do with the operating system. I'm currently using a USB keyboard which functions fine. If anyone has advice, please respond. I apologize if this was hard to follow. If you have questions about anything I said I'd be happy to clarify. Thank you!

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