{process name} ({process id}) An attempt to determine the minimum I/O block size for the volume “{name}” containing “{file name}” failed with system error {error code}: “{error message}”. The operation will fail with error {error code}.

Details
Product:	Exchange
Event ID:	491
Source:	ESE98
Version:	6.0
Component:	Extensible Store Engine
Symbolic Name:	OSFS_SECTOR_SIZE_ERROR_ID
Message:	{process name} ({process id}) An attempt to determine the minimum I/O block size for the volume “{name}” containing “{file name}” failed with system error {error code}: “{error message}”. The operation will fail with error {error code}.

Explanation
An unexpected error was encountered while trying to use the volume specified in the message.

User Action
Review the path name you attempted to use. Use the Error.exe utility to resolve system errors. For more information about the error code reference specified in the message, go to www.reskit.com.