I got a new Mac and it won’t let me sign in to my Apple ID even though I have the correct username and password. It says it’s incorrect, but I’m logged in on my phone and other devices using that same username and password. The Mac itself is old, but it’s new to me. I’m trying to update it, but it won’t let me because I can’t sign in to Apple ID.
MacBook Air 13″, OS X 10.10
You need your Mac user account, that is your login user name to your MacBook Air.
See the following Apple articles:
If you forgot your Mac login password -> https://support.apple.com/en-us/HT202860
Change the login password on Mac -> https://support.apple.com/en-gb/guide/mac-help/mchlp1550/mac
Reset your Mac login password -> https://support.apple.com/en-mn/guide/mac-help/mh35902/mac
If you can't reset your Mac login password -> https://support.apple.com/en-gb/HT212190
See also -> Ways to remember passwords on Mac
Ways to remember passwords on Mac – Apple Support (UK)
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BTW:
You are sign in here . . . with your Apple ID & Password.
Your Apple ID is the personal account you use with all Apple products and services. It includes the email address and password you use to sign in, as well as the contact, payment, and security details that you use with Apple.
You can’t merge multiple Apple ID accounts.
What happens when you use the same Apple ID & Password that you use to sign in here?
See -> Sign in with your Apple ID -> Sign in with your Apple ID - Apple Support
Apple ID Login
