After moving users or making other admin changes that following error occurs:
The application configuration name specified is invalid (DA12). You entered: POA.
Any future admin changes after this error will not process. Admin messages backup in the wpcsout/ads/2 directory.l
The next time the POA is restarted it will not load and reports an error 8101.
This can happen when another MTA in the system is misconfigured and has the same IP address and port as the POA with the problem. Admin messages destined for the MTA get sent to the POA and processed by the POA's admin thread. This writes incorrect information about the post office to the WPHOST.DB causing any future changes to this post office to fail.
A rebuild of the WPHOST.DB will allow the POA to load properly until the next set of admin changes are received by the POA.
Things to check:
1) Connect to the primary domain in ConsoleOne and look for pending operations to an MTA. It is possible that the MTA's IP address had been changed to be different from the POA, but was not able to be completed (maybe the MTA was down or not reachable).
2) Check the primary domain's HTTP page and look at the IP addresses and ports for each of the secondary domains to see if any of them are using the same IP address and port currently being used by the problem POA.
To fix the problem, unload the problem POA and then connect to the MTA with the incorrect IP address and port and change it to a valid one that is unique to the system, then load the MTA to propagate the information about the new IP address to the rest of the system. Once the change has reached domain that owns the problem post office, rebuild the problem post office database and load the POA again.