i got the error code 2003F when trying to reboot my computer after performing disk utility. I want to reinstall macOS. HELP!

There is something amiss with your wireless Internet connection that is not allowing you to use Internet Recovery mode to re-install macOS.

If any of the following are true about your network connection, you will not be able to reinstall macOS using Internet Recovery Mode:

• The wireless network is configured to use a hidden (non-broadcast) network name or SSID.
• The wireless network is secured with either WEP or WPA-Enterprise.
• The connection requires certificate-based authentication / 802.1x
• The connection requires the use of Proxies (where specific proxy servers must be configured in network preferences)
• Captive Wi-Fi networks (where you click an “Agree” button to access the Internet)
• PPPoE (where there is no router handling the PPPoE connection)
• Failure of the router to provide a workable DNS server address, or providing 0.0.0.0. This typically is seen with a -2002f or -2003f error message.

... and, if that is the case, you should try again with your notebook connected directly to your Internet router by Ethernet. This is where a USB-to-Ethernet adapter would come in handy. If you don't have one or don't want to purchase on, try visiting a friend or relative that have Internet service and try there. Alternatively, visit your local Apple Store or Apple Authorized Service Provider to assist you with this issue.

I also got -2003F error showing. On 2nd boot up i just held Command R down longer (for no particular reason) and got a nice surprise when it asked me to select and log on to my home internet connection. After a brief download, I'm back in the game.

I had to take my computer into my local computer place (I cannot think of a better word X( ) and they had to completely restart my computer to as if it was brand new. It cost around $200...

i cannot get mine to not give the -2003f code also. I cannot get it to any other recovery option than “Internet Recovery” after about 20 minutes of loading on the globe, it errors out with a -2003f. I’ve tried everything with my router.

I ended up on the phone with Apple and after trying many things she was able to get my computer to "find" my Mac HD data and from there was able to download the OS again. Apparently when I used my disk utility I erased something which kept my computer from recognizing my Mac HD data. I was fortunate and was able trade my old computer in. I would contact Apple again and see if you can get someone else that can help. Good luck to you!

What next? After u hold command r down ??

That is what originally I was trying to do. Restore to original out of box condition so that I would wipe all my data and be able to trade in. Unfortunately I believe I erased the original OS. Thankful I was able to get someone from Apple to help me with it. Happy that you were able to restore yours too!

Since following Apple instructions, will they not give the credit on the trade-in? I was going to just send mine in without an OS. Apple told me on the phone that they would install an OS either way and since it was their instructions that caused the problem.....

Same

Were you ever able to resolve your issue? I am having the same problem.

Have not resolved the issue. Wiped out data using disk utility. On phone with Apple for several hours--they don't know. OS system will not install. Need an OS sytem to trade in the old computer.

Thank you!!! I just boxed it up and was going to send it in. 6 hours to try to fix something that was not initially wrong was beyond my limit I think-LOL.

They suggested me to take the computer in, too. But most of the places where I live are all closed due to COVID.

I know! Takes so much time and patience, which the older I get the less I have ;)