How to change a password after getting the error: failed to change user password?

[John Gibson]

Only one user is able log into confluence.  They are using the proper credentials.  When attempting to change a users password the admin get the following error:

The following error(s) occurred:

• Failed to change user password. Check your server logs for more information.

Any help with this would be great.  Thanks.

[Radek Dostál]

What do the logs say?

(This should be in your <confluence data folder>/logs/atlassian-confluence.log)