To prevent Antivirus scanners from interfering with the operation of Lync its recommended that certain Lync processes and directories are excluded from the scan locations. This is recommended for each Lync Server role.

Lync Server 2010 Processes to exclude from antivirus scanning are:
  • ASMCUSvc.exe
  • AVMCUSvc.exe
  • DataMCUSvc.exe
  • DataProxy.exe
  • FileTransferAgent.exe
  • IMMCUSvc.exe
  • MasterReplicatorAgent.exe
  • MediaRelaySvc.exe
  • MediationServerSvc.exe
  • MeetingMCUSvc.exe
  • MRASSvc.exe
  • OcsAppServerHost.exe
  • QmsSvc.exe
  • ReplicaReplicatorAgent.exe
  • RTCArch.exe
  • RtcCdr.exe
  • RTCSrv.exe
IIS processes to exclude from antivirus scanning are:
  • %systemroot%\system32\inetsrv\w3wp.exe
  • %systemroot%\SysWOW64\inetsrv\w3wp.exe

SQL Server processes to exclude from antivirus scanning are:

  • %ProgramFiles%\Microsoft SQL Server\MSSQL10.MSSQLSERVER\MSSQL\Binn\SQLServr.exe
  • %ProgramFiles%\Microsoft SQL Server\MSRS10.MSSQLSERVER\Reporting Services\ReportServer\Bin\ReportingServicesService.exe
  • %ProgramFiles%\Microsoft SQL Server\MSAS10.MSSQLSERVER\OLAP\Bin\MSMDSrv.exe

Directories and files to exclude from antivirus scanning are:

  • %systemroot%\System32\LogFiles
  • %systemroot%\SysWow64\LogFiles
  • %systemroot%\Windows\Assembly\GAC_MSIL
  • %programfiles%\Microsoft Lync Server 2010
  • %programfiles%\commonfiles\Microsoft Lync Server 2010
  • %SystemDrive%\RtcReplicaRoot
  • Lync File share store
  • SQL Server data and log files, including those for the back-end database, user store, archiving store, monitoring store, and application store.  

As per microsoft reference here