A path error occurred, but no further information about the error is available. Errors occurred because of an outstanding I/O request being purged. For example, an ACB for an application which has outstanding I/O requests received INOP, or an operator entered VARY INACT for resources that had outstanding I/O requests.
VTAM® hint: If you receive this code when attempting to send data over an active Enterprise Extender PU, ensure that UDP ports 12001 and 12004 on all firewalls in the path of the IP traffic are open and allowing the traffic through.