Exchange Server 2010 & Event ID 106

There is nothing to worry about this error. Microsoft published article KB982679 - Event ID 106 is logged when you start the RPC Client Access service on Exchange Server 2010.
This problem occurs because the performance counters of the RPC Client Access service are not installed when you install only the Mailbox role on an Exchange Server 2010 server. However, this does not affect the functionality of the Exchange Server 2010 server.
It’s not so pretty to see many errors in Event Viewer after restarting Microsoft Exchange RPC Client Access service. Let’s try to manually add RPC Client Access performance counters.
Manually add RPC Client Access performance counters

• Start Exchange Management Shell
• Add-PSSnapin Microsoft.Exchange.Management.PowerShell.Setup
• New-PerfCounters -DefinitionFileName "C:\Program Files\Microsoft\Exchange Server\V14\Setup\Perf\RpcClientAccessPerformanceCounters.xml"
  
  
• Restart server or Microsoft Exchange RPC Client Access service.