Have you ever tried to bring up the CA Dispatch started task but during startup, it abends with a S878?
A review of the CA Dispatch logs shows that you received a IEA705I ERROR DURING GETMAIN SYS CODE = 878-10.
You haven't made any changes to any of the Dispatch related internal IDMS storage settings or to the Dispatch REGION setting. So what caused the abend?
The first thing you should check, believe it or not, is the BLOCK SIZE setting on the Dispatch 11.7 installed CADSOPTN library. If the block size of the CADSOPTN file is anything other than the REQUIRED value of 3120 then this is the likely cause of the S878-10 abend. To resolve the problem, you need to reblock the CADSOPTN library back to it's original installed value of 3120 and then restart the CA Dispatch started task.
A TSO or ISPF 3.4.S or 3.4.I function can be used to display the CADSOPTN library attributes including the block size.
The permanent resolution is to disable or otherwise prevent any 3rd party packages that reblock libraries or files, to something that the software thinks is a more efficient block size, from manipulating any of the CA Dispatch related libraries or files.