If you are using Microsoft Windows Vista or XP on your MacBook, MacBook Pro, or MacBook Air with a Multi-Touch trackpad, you may have difficulty using the trackpad to select or drag items on the screen. You may notice any of the following: When using your thumb to click an item the cursor may move slightly and not select the intended item. The cursor may shake when you press or remove your finger from the trackpad. If you press down with your thumb, then use your finger to select or drag an item, the cursor may unexpectedly release.
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