COF10306I COMMAND SYSTEM ERROR. service-routine ERROR CODE xxxx.
Explanation
Either the TSO/E parse service routine or the TSO catalog information routine was not able to perform its normal function.
System action
Processing continues with no change made to VLF storage.
User response
See the description of the indicated service-routine in z/OS TSO/E Programming Services for an explanation of the displayed error code and information about how to correct the condition.
Source
VLFNOTE