X11 connection rejected

[Patrick Dupre]

Hello,

On a machine I can ssh -X and run xclock for example, but
 sudo system-config-users
gives

(process:5034): Gtk-WARNING **: 14:59:07.212: Locale not supported by C library.
    Using the fallback 'C' locale.
X11 connection rejected because of wrong authentication.
system-config-users requires a currently running X server.
GtkWarning: 'could not open display'

Is there a solution?

Thanks
===========================================================================
 Patrick DUPRÉ                                 | | email: [e-mail]
 Laboratoire interdisciplinaire Carnot de Bourgogne
 9 Avenue Alain Savary, BP 47870, 21078 DIJON Cedex FRANCE
 Tel: [phone]
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