On access scanning Missing file check in Attachment Checker is a marker to let the app know if it has been enabled in the 3rd party virus scanner.
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Users will only find out when they try to preview or download the attachment, which will redirect them to a dead link.
If on access scanning missing file check is enabled, a comment will then be added as a feedback to users that the file has been deleted.
If delete virus files infected file is enabled, the attachment record will also be deleted from the database.
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The on access scanning missing file check can be enabled at Attachment Checker Configuration → Virus Scanning
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