What is error -2100F for MacBook Pro A1286

Hello there StevenYashWrites,

We understand your MacBook Pro isn't starting up as expected, and you're seeing an error that shows -2100F. We're glad you've taken the time to connect with us here in Apple Support Communities, and we'd like to learn more to see how we can help.

To begin, what are seeing on the screen of your Mac in addition to the error code? Based on the error you're seeing, this sounds like a network-related issue. Have a look at this support article and let us know if you're seeing any of these specific screens:

If your Mac doesn't start up all the way

If you're seeing a globe with an alert symbol, the 'If you can't start up from macOS Recovery' section of this support article should help:

About macOS Recovery on Intel-based Mac computers

Let us know what you find. We'll take a closer look from there, and continue working together to sort this out.

Cheers.

Ok I had error -2100F on my iMac 2010. It tried to do Internet Recovery and that was the error code after a considerable time. This code is for wifi connections. error -2103F is for when connected directly via ethernet.

I could find no solutions on the web so I guessed that there was problem with my hard drive. I removed my hard drive following Youtube info to open iMac. I had a spare data drive from a Windows PC which I formatted on another Mac to APFS - this step is possibly not necessary. I then fitted the drive and booted up iMac with command option R. Internet recovery started pretty quickly now and gave me the menu choices. I restored from a Time Machine backup and after about 5 hours all working ok.

Grant Bennet-Alder's response in this older thread may prove useful:

What is -2100F error mean while trying to… - Apple Community