Fix Windows Server R2 2012 Windows Search Indexer Hanging or Not Responding

We've encountered this issue at two clients running 2012 R2, although it may apply to other versions of Windows Server. Add the following registry entry to limit the search indexer core count to 1. For whatever reason this fixes the issue.

[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows Search]
"CoreCount"=dword:00000001

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