Why is it when I'm typing a email and have to go back and add a letter, each letter I type erases as I?

write a new letter. For example I wrote"


The grl when to the pool.


YOU SEE I FORGOT TO BUT THE LETTER "i" in GIRL.


Then I go back to fix the problem and for some reason as I type i THE R THEN L DISAPPERS. If that makes since!


Then I have to erase and start again.
Why is it when I'm typing a email and have to go back and add a letter, each letter I type erases as I?
try pressing the insert button on your keyboard. you might have toggled it to type over the next letter instead of inserting a new letter.
Reply:Maybe the "Insert" Key was active as it can Overwrite or Insert accordingly.
Reply:You have "insert" turned off on your keyboard. Press the "insert" key one time, and try it again.