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I want to safely change the "full name" for my account. (I only want to change the "full name" – not the "account name" aka "short username").

But, after modifying the field (shown below) and before clicking "OK", this warning shows up:

WARNING: Changing these settings might damage this account and prevent the user from logging in. You must...

How and why would/could this damage my account?

Users & Groups dialog screenshot

Pup
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1 Answers1

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There is no danger in changing the user's full name in this dialog. Some of the settings on this pane could mess things up. For example:

  • It's possible to change your shell to something that doesn't exist
  • Changing your user id can mean that you can't access your files, since they are owned by the old id
  • Changing the short username might affect all sorts of weird things, since many apps may depend on your username staying the same.
Alan Shutko
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  • The short name should be OK as well. Unix used the od as you note and scripts should not be using your name in the path but things like ~ or $HOME to find your home. But check that changing the short name does not change the home directory name – mmmmmm Aug 16 '16 at 19:55
  • @Mark Changing the account name (aka short name) can cause loss of group membership, including the loss of admin privilege. See "Changing my administrator user's username has removed privileges". – Gordon Davisson Jul 21 '18 at 18:32
  • @GordonDavisson I though groups and permissions were related to userids only ir if the ids match the the names do not matter (or is that pure Unix thinking and Apple user management adds something . As for the other question I would like to see some dscl info to confirm one way or another. – mmmmmm Jul 21 '18 at 18:55
  • @Mark In unix (both macOS and traditional), there are two different kinds of group membership: a user's primary group is identified by the group ID number being listed in the user's record, and additional groups are identified by the user's short name being listed in the group record. macOS stores the records differently (files in /var/db/dslocal vs /etc/{passwd,group}), but the basic logic is the same. Change a user's short name, it doesn't match what's in the group record(s), they lose all non-primary groups. Try dscl /Search -read /Groups/admin GroupMembership to see. – Gordon Davisson Jul 21 '18 at 19:42
  • BTW, macOS also lists group members' UUIDs in the group record (try dscl /Search -read /Groups/admin GroupMembers), but doesn't seem to actually use this data. – Gordon Davisson Jul 21 '18 at 19:43
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    Is this answer correct? Why no upvotes? – gen Nov 10 '18 at 12:23
  • Hi, what is this user ID and Group? – Suryakant Mar 21 '20 at 16:35