How do I disable mouse acceleration?

Boot into Safe Mode according to Start up your Mac in safe mode - Apple Support and reset the mouse Tracking Speed in the System/Mouse/Point & Click preference pane.

Reboot normally and test.

NOTE: Safe Mode boot can take up to 10 minutes as it's doing the following; 

• Verifies your startup disk and attempts to repair directory issues, if needed

• Loads only required kernel extensions (prevents 3rd party kernel/extensions from loading)

• Prevents Startup Items and Login Items from opening automatically

• Disables user-installed fonts 

• Deletes font caches, kernel cache, and other system cache files

Would think the right place to look is System Preferences >>> Mouse.

That is where to start unless this is a Third Party Mouse with Third Party software required to make it function.

Vicor S wrote:

The correct answer is: "it's not possible". This is an issues that has not had a solution for a very long time. I'm just refreshing Apple's memory that they ***** at giving user basic options.

Then sell your Apple gear and move on. Why continue to use something you find useless?

Log into a basic admin user account, Set up users, guests, and groups on Mac,  and see if the problem persists. This tells us if the problem is limited to your user account or is system wide.

Advise and possible solutions are offered in good faith and on a volunteer basis.

User wrote " Maybe Apple *should* look at what issues the community forums have. " that has already been covered earlier

Firstly , Apple is not here and will never hear you comments. The ASC Forums are only Apple users helping Apple users.

What is the issue? What exactly do you mean by "mouse acceleration"?

Perhaps if you explain what is that you don't like about how the mouse works it will be clearer to all of us.