Change the text cursor/caret in Visual Studio 2010

To clarify there are two modes when using the editor: Insert and Overwrite.

Insert -- the "normal" thin caret that inserts characters as you type.

Overwrite -- the "fat" caret that will overwrite any previous characters as you type.

These two act the same when at the end of your document and you are just typing but go in the middle of some text and use them then you will see the difference.

Press the Insert Key

If you are using a laptop keyboard also Shift+0 will solve your problem.