Either a system call failed in the operating system or the command that was executed exited with a non-zero status.
The following example shows a statement that might cause the system command to fail with an error:
SYSTEM 'hello';
Make sure that the system command is not trying to run a function or program that is not in your path or that is not applicable to the environment.
Make sure that you have provided a user ID and password when connecting to the database server. The database server must have the user's password in order to execute a command on behalf of that user.
On Windows platforms, make sure the following Advanced User Rights have been assigned to user "informix": Act as part of the operating system; Increase quotas; Replace a process level token.
The following example shows a statement that will fails with error -668 and the ISAM error explanation '-255 Not in a transaction':
SYSTEM 'exit 255';