Hello @abrar,
Are you positive the s3:DeleteObject
permission is set for the bucket in question? If not, that would certainly explain it. If you believe it is set, are you able to delete files from this bucket using the AWS CLI client?
Please also see:
https://docs.aws.amazon.com/AmazonS3/latest/dev/using-with-s3-actions.html
The Kaltura Server implementation for deleting a file over S3 is here:
/opt/kaltura/app/infra/storage/file_transfer_managers/s3Mgr.class.php
protected function doDelFile ($remote_file)
You can add some debug prints to further diagnose the issue.