Knowledge Base

Problem

A user attempts to restore an EthoVision experiment from a backup file but encounters an error during loading, or EthoVision becomes unresponsive (hangs) when trying to open a large backup file.

Details

EthoVision XT creates backup files (.evb or similar) that can be used to restore experiments. However, very large backup files — typically from experiments with many trials, long recordings, or large raw datasets — can cause EthoVision to hang or become unresponsive during the restore process. In some cases an explicit error is shown; in others the application simply stops responding. This is a known limitation with large backups. Smaller backups typically restore successfully. The issue is distinct from corrupted database errors (which show explicit error messages immediately). Affects EthoVision XT across versions when backup files are very large.

Solution

1. Before attempting to open a large backup, ensure your computer meets or exceeds the recommended hardware specifications for EthoVision XT (particularly RAM and storage speed — SSD recommended).
2. Close all other applications to free up system RAM before attempting to restore the backup.
3. Attempt to open the backup file and wait — for very large backups, EthoVision may appear unresponsive for an extended period (10–30+ minutes) before completing the restore. Do not force-close the application unless it has been unresponsive for more than 30 minutes.
4. If EthoVision consistently fails to restore a large backup, try the following:
a. Copy the backup file to a local SSD drive (not a network drive) before opening.
b. If the backup contains multiple experiments, check whether Noldus support can assist in splitting or extracting specific experiments from the backup.
5. If an explicit error is shown immediately on opening (not just unresponsiveness), refer to the 'EthoVision Experiment File Fails to Open – Database or File Error' article for database-specific troubleshooting.
6. Contact Noldus technical support if the backup cannot be restored — provide the backup file size and the exact error message or behavior observed.