Edit a sentence and add text

Recently, if I want to edit a sentence and add text in the middle of the sentence, eM Client types over the existing text instead of adding to it. Can’t find any setting to change this, VERY annoying!!

Hello, do you mean that if you type starting the place where you focus the cursor starts to be rewritten while you type? This can be caused by the “Insert” button on your keyboard. If you’re selecting the whole sentence and the start typing or insert the text using the paste feature, the selected text should be rewritten.