Sometimes when using Word I accidently press Insert on the
keyboard instead of delete when removing characters. This
causes problems for the whole document because once I have
done this I can no longer edit words or sentences properly.

For example if i had the letters bt and the word was
supposed to be bat. I can not add the a between the b and
the t. Word will not allow me to put a space between the b
and the t to fix it. If i hit space it will go over the t
and therfore ruin the spacing between the whole sentence.

This only happens when I accidently hit the insert key. Is
there a way to undo whatever the insert key has done. Any
help appreciated