Knowledge

ERROR_FILEMARK_DETECTED - 1101 (0x44D)

A tape access reached a filemark.

Updated: Feb 21, 2026

Technical Background

This error code is specific to tape drive operations and indicates that a read or write operation has encountered a filemark on the tape. A filemark, in this context, signifies the end of a logical data unit or file stored on the tape.

Error Details

  • Error Name: ERROR_FILEMARK_DETECTED
  • Numeric Code: 1101 (0x44D)
  • Short Description: A tape access reached a filemark.

This error typically occurs during data read or write operations on magnetic tape storage devices. The presence of a filemark indicates that the end of a specific logical unit has been reached, which can be used to manage and organize data stored on the tape.

Common Causes

  • Invalid Parameter Values: Incorrect parameters passed to the API call may lead to unexpected behavior, including encountering a filemark prematurely or later than expected.
  • Incorrect Object Type: The operation being performed is not compatible with the current state of the tape. For example, attempting to write data when a filemark has already been encountered.

Real-World Context

Tape drives are used for long-term archival storage due to their high capacity and low cost per gigabyte. Filemarks are essential for managing data on tapes as they allow for logical segmentation of the tape into individual files or segments, making it easier to locate specific pieces of information.

Is This Error Critical?

The criticality of this error depends on the context in which it occurs. If the operation is part of a backup process, encountering a filemark may be expected and handled appropriately by the system. However, if the operation is intended to read or write specific data, an unexpected encounter with a filemark could indicate a problem that needs further investigation.

How to Diagnose

  1. Review Operation Context: Ensure that the tape drive operations are being performed in the correct context and that the appropriate commands are being issued.
  2. Validate Parameters: Check the parameters passed to the API calls for correctness, including filemarks and other logical markers on the tape.
  3. Confirm Object Types: Verify that the operation is compatible with the current state of the tape. For example, ensure that write operations are not attempted after a filemark has been encountered.

How to Resolve

  1. Correct Parameter Usage: Ensure that all parameters used in API calls are correct and appropriate for the intended operation.
  2. Adjust Operation Context: If the context is incorrect, adjust it to match the expected state of the tape drive.
  3. Restore Data: In cases where data integrity may be compromised, restore the data from a backup or reinitialize the tape as necessary.
  4. Retry Operation with Valid Inputs: Attempt to perform the operation again with valid inputs and parameters.

Developer Notes

Developers should handle this error by ensuring that their code can gracefully manage filemarks during read and write operations on tapes. This includes validating input data, handling logical markers correctly, and providing appropriate feedback or recovery mechanisms when encountering unexpected conditions.

Related Errors

  • ERROR_END_OF_MEDIA: Indicates the end of the tape has been reached.
  • ERROR_WRITE_FAULT: Occurs when a write operation fails due to hardware issues.
  • ERROR_READ_FAULT: Occurs when a read operation fails due to hardware issues.

FAQ

Q: What does ERROR_FILEMARK_DETECTED mean?

A: This error indicates that a tape access has reached a filemark, which is a logical marker indicating the end of a data unit on the tape.

Q: How can I handle this error in my application?

A: Ensure that your code correctly handles filemarks and other logical markers during read and write operations. Validate parameters and adjust operation context as necessary to avoid encountering unexpected conditions.

Summary

ERROR_FILEMARK_DETECTED is a specific error code indicating the end of a data unit on a tape drive. Developers should handle this error by ensuring that their applications can manage filemarks correctly, validate input parameters, and adjust operations as needed to maintain data integrity and system stability.