SOLVED MacOS 10.10.4 yosamite trouble updating to big sur

[Spacemonkey9695]

Hi my sister has a mac mini(late 2014) running macOS yosamite 10.10.4, I'm trying to help her upgrade to big sur but the previous owner account is still logged in. When setting up the mac he gave her the password however now she's lost it and we cant update to big sur while other user is logged in.

I am not very experienced with macOS but
I have tried killing loginwindow process through activity monitor and terminal but it doesn't work I have also tried restarting the mac and the other user is still logged in.

Is there any way i can log this user out without password or update to big sur without logging him out.

Any help is appreciated I'm a tech nerd so should be able to follow any instructions but have no experience with macOS.

 

[Lufbrarunner]

Apple includes a tool to replace a Mac's password. This is the best option if you have completely forgotten your password. Follow these steps:

1. Turn off your Mac (choose Apple > Shut Down).
2. Press the power button while holding down Command + R. The Mac will boot into Recovery mode
3. When you see the load bar appear you can let go of the keys. It may take a few minutes to load.
4. Select Utilities
5. Choose Utilities > Terminal.
6. Enter resetpassword (all one word, lower-case letters) and press Return.
7. Select the volume containing the account (normally this will be your main hard drive).
8. Choose the account to change with Select the User Account.
9. Enter a new password and re-enter it into the password fields.
10. Enter a new password hint related to the password.
11. Click Save.
12. A warning will appear that the password has changed, but not the Keychain Password. Click OK.
13. Click Apple > Shut Down.

Now start up the Mac. You can log in using the new password.

 

[Spacemonkey9695]

Thank you very much I'm going to my sisters in an hour will try it an see if it works.

Thanks.

 

[Spacemonkey9695]

Worked perfectly,

Thank you

 

[Lufbrarunner]

Glad that you are sorted.

 

[MartyByrde]

Couple of things to be aware of:

1. She took a HUGE jump in terms of just upgrading in place, from Yosemite to Big Sur. That could lead to issues.
2. If he uses any third party software, will need to check with compatibility with Big Sur. A number of them are not yet compatible (I have 5 of them, and that's one of the reasons why I have yet to move to Big Sur from Catalina).
3. Big Sur just came out, and as is typical with each new Mac OS, it contains a number of bugs/has some issues.
4. A beta for the next version has already been released, and that next version, V11.1.0, could be released by next week. I do not know what it fixes/corrects/contains, etc. But such a quick release so close to the first version is nota good sign, at least not for me.

I am also on two other Mac discussion sites, and am seeing numerous issues that folks are having.

 

[Spacemonkey9695]

Thanks for the info I will let her know, she mostly uses it for her business, mostly printing and file management. No third party software.