BSYR127E Invalid command - Please enter "D" to display all data sets using this alias, "M" to mergecat this alias into another catalog, or "R" to rename all IMS object data sets using this alias.

Explanation

An invalid line command was entered.

User response

Enter D to display all the data sets using the alias. Enter M to perform a MERGECAT to move this alias from one MVS usercat into another. Enter R to rename all the IMS database data sets using this alias.