I would advise you to open a support ticket with IBM.
When that error has been seen before, I believe one of the action plans was to cancel the recovery key operation and retry via CLI (prepare, confirm, commit). However, without understanding the cause of the error then it is not possible to say if that would be appropriate here.
The CLI steps would be:
chencryption -recoverykey newkey -key cancel
and then prepare again using either the GUI or the CLI:
chencryption -recoverykey newkey -key prepare
chencryption -recoverykey newkey -key confirm
chencryption -recoverykey newkey -key commit
Support would be able to advise you.
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Chris Canto
Software Developer
IBM
Hursley
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