I use Cisco Systems' Cisco Unity voicemail. After replacing my Active Directory (AD) schema master, I can no longer create new voicemail accounts. Existing voicemail accounts seem to work fine, and I know AD is replicating as it should. What's happening?

The problem probably has more to do with your Global Catalog (GC) server than with the schema master. My guess is that your schema master was, in fact, a GC server.

When you install Cisco Unity, it looks for a GC server and creates a registry entry pointing to that server. Unfortunately, when you delete the GC server referred to in the Cisco Unity registry settings, the product doesn't dynamically poll for a new GC server. Instead, you must manually change the registry entry to point to another server.

To correct the Cisco Unity registry entry, launch a registry editor and go to the HKEY_LOCAL_MACHINE/SOFTWARE/Active Voice/Directory Connector/DirSynchGlobalCatalog/1.00/Directory registry subkey. You should see an entry called DefaultGlobalCatalogServer; this entry's value will be your previous GC server's name. Change the value to the name of your new GC server; be sure to use the Fully Qualified Domain Name (FQDN—e.g., server@yourdomain.com). You don't need to reboot Cisco Unity for this change to go into effect.