this are some examples
mail1
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The message below (subject: "RE: e-mail issue") that you sent was not delivered because it contained one or more prohibited attachments. The prohibited attachment filenames are below:
- "img-Y271731-0001.pdf.pdf" was prohibited
- "img-Y271731-0001.pdf.pdf" was prohibited
mail2
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unreadable format for the attachment.please resend as a PDF file
mail3
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I CAN VIEW THIS..........the file name is XXXX.pdf.pdf.pdf