Both the installer and upgrade for 4.0.16 include 'sechash', so it is not clear to me how this error is arising for you. If this is a new installation, did you have any problems while installing? If this is an upgrade, did you have any problems while upgrading?
You can create sechash manually with a MySQL query:
Code:
ALTER TABLE vw_subscribe
ADD COLUMN sechash VARCHAR(40) NOT NULL DEFAULT ''