After migrating from a previous-generation Macintosh model to a newer laptop that has some form of multitouch support in the trackpad, several people have found the two-finger scrolling doesn't appear to work.
Apple Discussion poster "woojoo" writes:
"I've replaced my iBook with an aluminum 2.0GHz MacBook just yesterday. I love the trackpad, but I seem to have a problem with two-finger scrolling: it doesn't scroll with two fingers."
In most cases, various multifingered gestures seem to work just fine, with only the two-finger scrolling not functioning properly.
This problem seems to happen only when people are migrating, and not with new hardware or when fresh system software is installed on the newer computers, which indicates the problem is a software setting and not a faulty trackpad. More than likely this is from the global preferences (which hold trackpad information) for the old computer being on the new one with a setting or some other format that is preventing the trackpad from working properly. Apple has made the global preferences file hidden by default, but you can use the terminal to enable the preference settings needed for two-finger scrolling.
1. Use the Terminal to enable proper scrolling behavior.
If you have just transferred your software and data to a new MacBook or MacBook Pro and are having troubles with two-finger gestures, then entering the following command in the Terminal should re-enable it:
After entering this command, either restart the computer or log out and log back in for the changes to take effect.Resources