I’m trying to use S3 CORS for my project and I’m encountering the error below:

An AJAX HTTP request terminated abnormally.
Debugging information follows.
Pagh: /system/ajax
StatusTest: n/a
ResponseText:
Error
Error message
Warning: filesize(): stat failed for s3://file-name.txt in file_save() (line 605 of /srv/bindings/ 8583c5f5083a475a9d644d64d843b077/code/includes/file.inc).
PDOException: SQLSTATE[2300]: Integrity constraint violation: 1062 Duplicate entry ‘s3://file-name.txt’ for key ‘uri’: INSERT INTO {file_managed} (uid, filename, uri, filemie, filesize, status, timestamp, type) VALUES (:db_insert_placeholder_0, :db_insert_placeholder_4, :db_insert_placeholder_5, :db_insert_placeholder_6, :db_insert_placeholder_7); Array(
[:db_insert_placeholder_0] = > 1
[:db_insert_placeholder_1] = > file-name.txt
[:db_insert_placeholder_2] = > s3://file-name.txt
[:db_insert_placeholder_3] = > text/plain
[:db_insert_placeholder_4] = > 0
[:db_insert_placeholder_5] = > 0
[:db_insert_placeholder_6] = > 1398930781
[:db_insert_placeholder_7] = > default
)
in drupal_write_record() (line 7211 of /srv/bindings/8583c5f5083a475a9d644d64d843b077/code/includes/common.inc).

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Below provided some of alternatives to check this error.

1. Insert the same filename into multiple times.
2. Cause of this issue can be having multiple CORS3 Upload fields on a single form.