CredentialProvider Change Password scenario

We are replacing the MS Password Provider with our own. I could not
find nor description neither any sample how to handle the change
password scenario on the web .

When the user presses the arrow button at the logon and unlock
scenarios the GetSerialization function is being invoked where we pass
back the parameters CPGSR_RETURN_CREDENTIAL_FINISHED with the
KerbInteractiveLogon or KerbWorkstationUnlockLogon message type and by
filling out the KERB_INTERACTIVE_LOGON or
KERB_INTERACTIVE_UNLOCK_LOGON structure.

What about the Change Password scenario? Which structure and which
message type should I give back to LogonUI? Should I change the
password myself?
If yes, then how do I get the screen that says the Password has been
changed successfully like in the MS Password Provider? On the msdn I
have read that CPGSR_NO_CREDENTIAL_FINISHED should be given back but
then there is no reaction when I press the arrow button.
Any tips or sample code on this issue? (Would be great if someone can
point to CREDUI scenario and Filter samples)

Thanks
IJ

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