The most common reason for this error (16 or 10) is that the file is password protected. Since AWARD® is unable to detect the file content, it generates the error.
The solution is to ensure the file is not password protected / encrypted or to enable unscanned uploads.
This is done via Project > Setup > Tools > Advanced Settings > Allow Unscanned Uploads
Note: You will need to be assigned the role of Project Manager to enable this function.
If you use "Allow Unscanned Uploads" to upload a file, it is strongly recommended that you re-enable scans afterwards.