I recently purchased a iMac and it was partially erased incorrectly there are no system preferences, no is system but they never deauthorized there Apple account on the iMac so I can’t install another anyone no how to bypass authentication and then go to a factory reset and hopefully reinstall system preferences?
iMac, OS X 10.11
Return that iMac to the seller and tell them to properly prepare it before trying to sell it to someone else.
see > What to do before you sell, give away, trade in, or recycle your Mac - Apple Support
Return that iMac to the seller and tell them to properly prepare it before trying to sell it to someone else.
see > What to do before you sell, give away, trade in, or recycle your Mac - Apple Support
If it will not boot into the Recovery Partition or do an Internet Recovery then you bought a boat anchor and there is no way to launch Mac OS on it.
Going forward if you must buy a used Mac only purchase Apple Refurbished Macs or buy from a trusted seller such as Macsales.com. NEVER EVER buy from Amazon, E-Bay, Craigslist, Nextdoor, Marketplace, your local PC shop etc.
Hi Beth_73,
What year and model is your iMac? You can find out by checking the serial number against Apple's warranty coverage website: Check Your Service and Support Coverage - Apple Support
To find the serial number: Identify your iMac model - Apple Support (CA)
Depending on what kind of iMac you have, there might be a way to get it back to working condition. This could involve using a bootable installer or restoring the firmware through a second Mac.
No operating system
