Any experts here??? Normally, typing here or on WORD, or in email, you can go back and insert something or correct, no problem. But occasionally, I apparently do something, I do NOT know what, that changes this so that when I go back to insert something, instead inserting it, it types over [erases] everything in front of my insert, letter by letter, as I type. I don't want to have to retype the whole page to make a correction at the beginning!!! Can anybody tell me what this is and how to change back to the previos mode of typing?