Dear customer
It must be said that this matter would be better handled in a support case.
Anyway, at the abending spot (LMOD BC1PACM6 CSECT BC1PACM6 +000842 at RMID = CSIQI00) endevor is calling the MVS "data in virtual" (DIV) services to open one of the ACM datasets. Abend S08B with reason code xxxx0038 from DIV services means that the dataset is not a VSAM linear dataset as it should be.
Your first step is therefore to get the name of the ACM datasets used in your run. In batch, add //EN$TROPT DD SYSOUT=* to the JCL to get an endevor options report. In foreground, use option 1 (DISPLAY), 3 (SITE) to see your default options. In both cases, scroll down to find:
ACM Index Root Data Set (normally prefix.ACMROOT)
ACM Index Xref Data Set (normally prefix.ACMXREF)
Pay attention to all the dataset names. They might be messed up in your C1DEFLTS.
Then take an IDCAMS LISTCAT of both datasets to see whether, in the ATTRIBUTES section, the string "LINEAR" shows up. The abend you are getting tells us that it is not there, at least for one of them.
Once you identify the dataset which is not a linear VSAM, define it with the right JCL (BC1JACMD)
Hope this helps
Regards - Eduard