Subversion Repositories LCARS

Error running this command: svn --non-interactive --config-dir /tmp list --xml -r 77 'file:////home/mw3020/f001/svn/LCARS/trunk/po@284'
warning: W160013: File not found: revision 284, path '/trunk/po'<br />
E200009: Could not list all targets because some targets don't exist