No. If the account already exists, it will need to be enabled another way. I have a post showing how the post-encryption enablement process works on both Mountain Lion and Mavericks:
http://derflounder.wordpress.com/2013/10/24/enabling-users-for-filevault-2-with-a-non-enabled-admin-user-does-not-work-in-mavericks/
I'll give this a shot. Thanks!
In my testing I've found that if you set up a policy to create an account and then enable FileVault for that account as well it'll just enable FileVault for it if the account already exists.
Now, I have already had FV2 enabled on my machines so that may have to do something with it.
He's what the log from the policy will tell you:
Executing Account Account TEST...
[STEP 1 of 0]
Error creating user: An account with the user name Admin already exists..
Adding user Admin to filevault
Adding user 'Admin' to existing FileVault
FileVault is On. FileVault master keychain appears to be installed.
Oh, here's an edit:
JSS 9.31
Mac Os X 10.9.4
2 accounts.
1 local admin, deployed at imaging. Added to FileVault after the standard account has been enabled. I'm adding it to FV with the process I described above.
1 standard user, added after imaging and binding to AD then FileVault 2 enabled.
@rtrouton Is there a way to enable this newly created account via command line, rather than the GUI in System Preferences? On your site, I see you mentioned that this functionality was removed in Mavericks. Is there still no workaround?
Ugh. Not sure I'd recommend it either. Thanks Rich..
@makander: That trick may have worked once, but not any more. We're running 10.11.6, and here's what happens when I use a policy to add an existing local admin account with FV access:
Executing Policy Add localnab admin account
Error creating user: An account with the user name localnab already exists..
That's it. It does not add the user to FileVault.
jamf nation is full of threads on this very topic -- how to add an existing admin account to filevault -- but none of the solutions described there work.
The frustrating thing is that I can add a new admin account with FV, I just can't enable FV for an existing admin user.