Where to find icloud encryption key?

[BLUEFROG]

Actually, if an encryption key has been specified it is already stored in Keychain Access.

See this…

Invalid Encryption key

Do a Spotlight search for Keychain and open the Keychain Access application. In the logins section on the left, look for a key named DEVONcloudy Encryption (name of service) like DEVONcloudy Encryption (Dropbox). Double-click it and check the Show password checkbox. You will be required to enter your Administrative password. (This is the password you use to log into your machine with.) Press Allow (or Always Allow, if desired) and the password will be shown. Take note of the password, then quit…

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