person sustaining loss through any omission, mistake or misfeasance of the Registrar or any other officer or clerk in the execution of their respective dies under this Act or by any error, omission or misdescription in any certificate of title or any entry or memorial in the Register Book or by the registration of any other person as proprietor, and who is barred by this Act from bringing an action of ejectment or other action for the recovery of the land, estate or interest, may, in any case in which the remedy by action for recovery of damages as herein provided is inapplicable, bring an action against the Government for recovery of damages; in estimating those damages, however, the value of all buildings and other improvements erected or made subsequently to the loss or deprivation shall be excluded.