Error "Trouble matching, error -2249 (could not find session)" during transfers and rebuilds and DST


Our Engineering team has tracked down a number of issues that arise due to Daylight Savings Time (DST) in Retrospect Backup 18. See below for how to resolve them as of Retrospect Backup 18.5.3:


If you see the following error:

Error -2249 (could not find session)

This error will happen with Retrospect Backup 18.0.0 through 18.5.1 after the time changes due to Daylight Saving Time (DST). To fix the issue, you will need to update to Retrospect Backup 18.5.3. If you continue to see the error, you will need to rebuild the catalog file. For example:

  1. Seeing this error when running a transfer script, the destination backup set will need to have its catalog file rebuilt. For the source backup set, if grooming was enabled the catalog file will need to be rebuilt before grooming can run successfully run on the set. If grooming was not enabled, a catalog rebuild is not necessary.

  2. Seeing this error during backup or restores.

To rebuild the catalog file, please see our tutorial on rebuilding the catalog file:


After rebuilding a catalog file of a tape set you may see the following logging.

[*] Scx::ArxStartSeg: could not find session date 5/6/2022 8:08:51.228 AM for SET NAME during rebuild

This means that during the catalog rebuild Retrospect was unable to find a backup session and it has been skipped so that the rest of the backup set could be rebuilt. You may also see the following issues with the rebuilt set.

  1. An orphaned snapshot under the snapshot tab of the backup set properties. This snapshot is not browsable or can be restored from.

  2. Seeing a snapshot that has no name and no files when trying to retrieve a snapshot from the snapshots tab of the backup set. Attempting to retrieve the snapshot will result in the following errors.

    Bad Backup Set header found: 0x41005400 at 1,182,890
    Error retrieving file: C:\ProgramData\Retrospect\RtrExec.dir\Exec-7\State\RetroSec.dat 5/6/2022 8:08:55 AM (0), error -1 (unknown)
    Bad Backup Set header found: 0x69007300 at 1,315,974
    Error retrieving file: C:\ProgramData\Retrospect\RtrExec.dir\Exec-7\State\RetroSnp.dat 5/6/2022 8:08:55 AM (0), error -1 (unknown)
    Can't retrieve Snapshot for session , 5/6/2022 8:08 AM, error -1101 (file/directory not found)
  3. Verifying the set after the rebuild will have the following errors and some files may not be verified.+

    Backup Set segment DST_Tape found at unexpected address 1,376,256: was expecting 1,179,648

Other snapshots can be restored from and accessed. It is recommended to restore or transfer any needed data and recycle the backup set.

Last Update: May 22, 2022