3028MSExchangeApplicationLogicExtensionApplication Scenario: ProcessKillBit. Failed to read killbit list file because of exception System.IO.IOException: The process cannot access the file 'D:\Program Files\Microsoft\Exchange Server\V15\ClientAccess\owa\prem\15.0.1178.9\ext\killbit\killbit.xml' because it is being used by another process.
at System.IO.__Error.WinIOError(Int32 errorCode, String maybeFullPath)
at System.IO.FileStream.Init(String path, FileMode mode, FileAccess access, Int32 rights, Boolean useRights, FileShare share, Int32 bufferSize, FileOptions options, SECURITY_ATTRIBUTES secAttrs, String msgPath, Boolean bFromProxy, Boolean useLongPath, Boolean checkHost)
at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share, Int32 bufferSize, FileOptions options, String msgPath, Boolean bFromProxy)
at System.IO.FileStream..ctor(String path, FileMode mode, FileAccess access, FileShare share)
at System.IO.File.Open(String path, FileMode mode, FileAccess access, FileShare share)
at Microsoft.Exchange.Data.ApplicationLogic.Extension.KillBitHelper.TryReadKillBitFile(Int32& refreshRate, DateTime& lastModifiedTime)
This warning does not seem to negatively affect Exchange Server operations, but it doesn't look like there is a fix to remove this warning from being logged.