Hi Jack,

As Frank suggested, the change of the channel number was one of the first attempts we tried.

I confirm that we changed the SUBMIT to another command and it didn't work.

We'll give it a try using a different server and the program you attached.

We're running A-Shell 7.0.1760.0 under Red Hat Enterprise Linux Release 9.4 (Plow)

Thank you very much and best regards.

That seems like the logical explanation. I just can't see how commenting out the XCALL SUBMIT would affect it, given that it is executing an external command, in another process, unrelated to A-Shell. Surely the external command cannot be stepping on an A-Shell file channel. Possibly the XCALL SUBMIT itself could be the culprit, but in that case, it should have shown up in my test program. I thought it might be that the input file (lisemp.dat) was somehow being referenced by one of the XCALL SUBMIT parameters, but I don't see any evidence of that in the ashlog FOPENS traces.