Running the UCFTSO CLIST in TSO as supplied in the SAMPJCL library fails with a U3907 abend code in the CALL to RHDCUCFT. The U3907 indicates IDMS failed to LOAD the required module IDMSSTRT when starting up.
Check that the IDMS loadlib is specified in the CDMSLIB concatenation or if there is no CDMSLIB, in the STEPLIB concatenation of the TSO PROC.
The U3907 abend can also be caused by the use of a PDSE library in the CDMSLIB concatenation. Either change the loadlib to be a PDS instead of a PDSE or remove the CDMSLIB DD statement so IDMS loads from STEPLIB. You can use a PDSE in the STEPLIB.