If a parent-relative file external is defined, using the ../ URL-shorthand notation in the externals definition, and a working working copy containing this external is switched to a different branch (which also contains the same externals definition), the working copy will fail to update itself after the switch. Error messages differ depending on the repository access method. This is the error message for ra_local: svn: warning: apr_err=SVN_ERR_FS_NOT_FOUND svn: warning: W160013: Working copy path 'gamma-ext' does not exist in repository subversion/svn/update-cmd.c:175: (apr_err=SVN_ERR_CL_ERROR_PROCESSING_EXTERNALS) svn: E205011: Failure occurred processing one or more externals definitions svn: warning: apr_err=SVN_ERR_FS_NOT_FOUND svn: warning: W160013: Working copy path 'gamma-ext' does not exist in repository subversion/svn/update-cmd.c:175: (apr_err=SVN_ERR_CL_ERROR_PROCESSING_EXTERNALS) svn: E205011: Failure occurred processing one or more externals definitions For ra_serf, the message looks like: svn: warning: apr_err=SVN_ERR_XML_MALFORMED svn: warning: W130003: The XML response contains invalid XML subversion/svn/update-cmd.c:175: (apr_err=SVN_ERR_CL_ERROR_PROCESSING_EXTERNALS) svn: E205011: Failure occurred processing one or more externals definitions svn: warning: apr_err=SVN_ERR_XML_MALFORMED svn: warning: W130003: The XML response contains invalid XML subversion/svn/update-cmd.c:175: (apr_err=SVN_ERR_CL_ERROR_PROCESSING_EXTERNALS) svn: E205011: Failure occurred processing one or more externals definitions