I am trying to install MacOS High Sierra on my 21 inch iMac 2013, but everytime I try to download it says the recovery server could not be contacted. I'm connected to a stable WiFi network and my iMac has the current date set.
If you can't download High Sierra while booted in Recovery mode, you might try creating a bootable installer on a usb flash drive and use that to install the OS. For this you'll need a flash drive that is at least 14GB.
Create a bootable installer - Apple Support
You can find a download link to the High Sierra full installer on this page:
How to download and install macOS - Apple Support
If you can't download High Sierra while booted in Recovery mode, you might try creating a bootable installer on a usb flash drive and use that to install the OS. For this you'll need a flash drive that is at least 14GB.
Create a bootable installer - Apple Support
You can find a download link to the High Sierra full installer on this page:
How to download and install macOS - Apple Support
iMac can't download MacOS
