Exact Error Message
Error on a request to space to end of data. The request could not be performed because of an I/O error.

Details:
The error occurs because the storage device driver did not receive a response from the storage device within a specific amount of time. The device driver contains time-out information for different media operations. One driver may have a longer time-out period than another. Installing a new device driver may extend the time-out period for media operations. If using a native Windows Driver, install the appropriate SYMANTEC  Backup Exec (tm) storage device driver instead.

If the problem occurs with the Backup Exec Storage Device Driver, call the manufacturer of the storage device to obtain the latest driver. The manufacturer's driver may have an even longer time-out period and be more suitable for the problematic system.

Related Documents:

245177: How do the "verify" and "write checksums to media" processes work and why are they necessary?
 http://support.veritas.com/docs/245177


246958: How to confirm that the data is being properly written to the tape media
 http://support.veritas.com/docs/246958


248089: A tape drive intermittently goes offline on the Backup Exec Devices tab, and "Event ID: 15. The device, \Device\SCSI\device_name is not ready for access yet" is recorded in the Event Viewer System log.
 http://support.veritas.com/docs/248089


255501: How to troubleshoot issues with a Robotic Library or Tape Drive in Backup Exec for Windows Servers.
 http://support.veritas.com/docs/255501

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