All signature operations are processed within the e-mail area of Activities. The most direct way to get there is to simply act as if you are creating an e-mail:
In the left navigation pane, click Home. Morningstar Office's home page opens.
In the left-hand column, click Activities. The Activities area opens in a new window. You will be in the Inbox.
Click . The New E-mail dialog opens.
Click . The Select Signature box opens.
In the Existing Signatures box, highlight the signature you want to delete and click . The signature is deleted.
Click to return to the e-mail.