We ran into an issue where the DTS packages extracting data using the Client
Access ODBC driver would not run when scheduled but would when simple
executed. The usual articles (authority issues) provided no resolution.
What we found was that if the NT profile on the server (which will be used
to attempt the connection) was more than the 10 character profile constraint
on the AS400, the DTS package ends with an unknown error.
Changing the Profile used to sign on to the server to a 10A profile, and
using the same profile (and security) on the AS400 resolved the issue.