Attachment refers to a file, usually added to emails, which can be sent in different formats.i

General information[edit]

An attachment is attached to an email and must be opened by the recipient. Text documents are sent as attachments most frequently, followed by PDFs, or Office documents. Attachments that have audio or video formats are also possible. Normally, all binary files can be sent as data attachments; from a technical point of view, attachments are found in the body. The body is the text body that contains elements like buttons, forms, or text. It is the second component of emails besides the header and shows the content of a message. It is possible to use formatted HTML text or binary data such as images [1].

Problems and risks with attachments[edit]

Not every attachment can be sent without problems. Most providers have size restrictions that affect audio or video formats in particular. However, size restrictions can now be easily circumvented either by using external providers that also allow larger attachments to be sent or by using cloud solutions offered by mail providers that allow the recipient to open the attachments via a link or download.


While the problem of size limitation is easily solvable, there is another problem that is not always as easy to handle. Experience shows that attachments are used again and again to place spam. Therefore, attachments may not reach your recipient at all because the entire mail ends up in the spam folder. Newsletters are often impacted by this problem. When sending images, it is, therefore, advisable to include them in the newsletter via an external server. The probability that the newsletter will be recognized and banned by the spam filter is significantly reduced. In general, extreme caution is advised with attachments from unknown senders, as they may always contain viruses or another malware and even with supposedly known senders, there is no guarantee that an attachment is harmless[2].

Personalized attachments[edit]

In online marketing, it is common knowledge that personalized emails or newsletters achieve a higher degree of effectiveness. The recipient's attention grows when they are addressed individually, and they usually read the incoming mail more precisely and with more focus.

Personalization can be achieved in different ways, for example in the subject line, an individually tailored greeting, or within complete content blocks. To increase the effectiveness of the personalized address by a further factor, attachments in the form of PDF documents can also be personalized. In marketing, such attachments are used to send customers invitations, coupons, brochures, tickets, or other offers. By addressing the recipient directly by name, the email with its attachment is perceived as being of higher quality and is, therefore, more likely to be read than a mail without the personalization.

Using personalized attachments as a PDF document instead of the text form or HTML offers several advantages:

  • The appearance of the attachment is independent of the email client used.
  • Recipients of text emails, on the other hand, often only see images or graphics.
  • The security factor is high because security settings can usually be used to completely prevent disclosure to unauthorized third parties.
  • Both archiving and printing the document do not require much effort.

Many companies often neglect personalized attachments because they fear that this would involve high logistical and financial costs. However, this fear cannot be supported, because the creation of personalized PDF attachments is easy to implement with a little technical skill. Additionally, in many cases, the implementation can be carried out within the company itself using existing personnel. This means that there are also no costs to be factored in from external providers [3].

Mail Attachment Downloader as a useful help for attachments[edit]

Attachments cannot always be opened directly or via a link or download. Attachments like invoice documents or other large documents are a challenge for the recipient, especially for companies, if they first have to expend effort to extract the attachments.

There are numerous programs on the market, some of them free of charge, which help to filter out email attachments from large volumes of data and open them without problems. Both hardware and software requirements are low, so the programs can be integrated into existing systems very easily. The functionality does not pose any major challenges to the mail recipient; after opening the program, a window pops up in which one enters the corresponding access data of the email address or the online account. In the next step, it is possible to select which user wants to open which attachments. Saving the attachments is also easy, one simply specifies a folder and saves the attachments [4]

Importance for online marketing[edit]

For most companies, attachments are a part of their daily business. Handling them properly is therefore crucial to ensure the corresponding processes work without obstacles. Whether and which tools are used depends on the size of the company and the type and number of attachments sent. In any case, it must be ensured that reliability, security, and deliverability are successfully integrated into everyday operations.


  1. Body Definition Computer Hope. Last opened 04.01.2021
  2. Attachment Definition Computer Hope. Last opened 04.01.2021
  3. Send a mass email with personalized attachments (in Gmail) GMass. Last opened 04.01.2021.
  4. Simplistic Yet Robust Mail Attachment Downloader App for macOS bitqueues. Last opened 04.01.2021.