Your project contains the old centralized "alert" system previously copied from upstream Bitcoin. This system lets the holders of a private key send messages to be displayed in the error field. Because of its limited utility, potential for abuse, known disclosure of the key to at least one untrustworthy party (and is believed to be compromised), and frequent use to justify other centralizing features this system has long been deactivated (and now is completely removed) upstream.

I would recommend you remove this system by adopting this code from upstream: https://github.com/bitcoin/bitcoin/pull/7692 or the parallel PR in bitcoin xt, https://github.com/bitcoinxt/bitcoinxt/pull/150