Is that error from ikeyman?
My first thought is to suggest you just
create a new server key. Since there is no historical data that is bound
to the old key (in contrast to a Notes keypair, for example), you can just
create a new one at any time. That probably gets you where you want to
be faster. If you don't want to do that for some reason, can you post the
exact steps you are performing that lead to the error?