Unexpected exception…. Data error (cyclic redundancy check)


[Error][New File] File=”XXXX.tmp” Error=”[com.ahsay.obc.core.bset.file.A] [BackupRequestTask.uploadFiles] Unexpected exception for sFilename=\\?\GLOBALROOT\Device\HarddiskVolumeShadowCopy52\XXXX sUploadPath=I:\XXXX.tmp sFileType=F, caused by [java.io.IOException] [ReadAheadInputStream.Reader.run]@829610816 Throwable=Data error (cyclic redundancy check). , caused by [java.io.IOException] Data error (cyclic redundancy check). “


This is due to corruption on the filesystem, commonly caused by failing hardware – most often by a disk with a bad block or failed RAID array that has had corruption propagated through to the data.


  1. Follow our guide on checking the event log for hardware issues to confirm that the underlying hardware does not have errors.
  2. Once the underlying hardware is confirmed to be healthy, run a chkdsk or similar filesystem integrity check.
  3. Identify the files from the error and try to read them independently to determine their integrity – deleting or repairing these files may be necessary.