Send password-protected attachments in Outlook

Given that business-critical information forms an important part of a company assets, and its leakage can lead to financial loss, damage or even legal action against the company, data loss protection solutions, and tools are essential to a corporate IT-environment. Although bulky and powerful DLP-suites from leaders of IT-security claim to protect from almost any risk, there is still much to be done on user-level, because there’s no other factor as powerful as human factor.

As long as files with sensitive content are stored on a duly protected corporate file server or endpoint, they can be considered quite safe. But when you send important documents via email that can pose a potential threat, even if we are speaking of an internal recipient. Ironically, the root cause of this threat is one of Outlook’s handy features you use so often without even noticing. The Auto-Complete feature saves your time and effort by adding the remaining part of the recipient address as you start to enter it in the TO field. Therefore, if you are short of time to double-check it, the attached document can fall into wrong hands. With a few hundred contacts on your list including colleagues, partners, customers, competitors, and just third parties, you run quite a risk of messing things up by unintentionally sharing a confidential corporate document, even if the wrong recipient is conscientious enough to inform you of the mistake and remove the file in question.

Secure attached files in Outlook emails

Step-by-step tutorial on setting up a rule to automatically encrypt files in outgoing Outlook messages – so that the email correspondence complies with the GDPR.

How to send Secure Email with Attachments in Outlook

One way of preventing confidential information loss is setting up automatic ZIP-archiving of outgoing attachments and protecting them with a multi-digit password. This can be done with the help of Attachments ZIP Compressor, one of the three elements of Attachments Processor for Outlook, a multifunctional solution by MAPILab that has an answer to almost any question you may have about sending and processing attached files.

As a matter of fact, this addon completely eliminates the need for an external WinZIP archiver when working with mail flow. It can compress your outgoing attachments, protect them with passwords, and unpack incoming files automatically, following a set of custom rules. Thus, you can set up a size threshold to archive large files or make sure all PDF or DOC files are compressed before sending, or auto-archive files that meet any other criteria of choice. Useful tip — remember to switch to Advanced Mode to create the rules.

However, before you create a lot of very exclusive filters for a few of your most important contacts or give up the entire idea because you are not a secret agent, after all, to spend this much time and effort on going through all those settings, let us take a quick glance on the pros of attachments archiving. No matter how confidential your data is, it is a good idea to archive most of the files in the mail flow on a permanent basis. First, you lower the load on resources, as compressed files consume less traffic and sending/receiving time. Next, archives also take up less disk space and prevent your .pst file from getting too bulky and slowing down your Outlook. Besides, using a comprehensive solution, such as the abovementioned Attachments Processor, you can optimize the storage of your incoming attachments and access to them, having them saved to a specific destination. All in all, archiving is not only a security measure but also an organizing tool.

Going back to security, though, one of the most impressive features of the addon is Password Manager. Not only can you set up separate passwords for different contacts and users, but you can also unpack incoming protected archives automatically if you happen to get a lot of archives with the same default password. What is more, you can protect outgoing files with a very complicated password and set up an automated unpacking of the archive on the recipient computer, so that he doesn’t have to re-enter the password. In this event, even if the file is sent to a wrong address, the data inside won’t be accessed by someone who is not supposed to see it.

As compared to the built-in Microsoft Office encryption capabilities, using Attachments ZIP Compressor to treat your incoming and outgoing attachments gives you two visible advantages. First, as we have said, its protection settings are flexible enough to protect both the sender and the recipient from having to enter the password every time they access the file. And second, not all file types support password protection, so it does make sense to safeguard and compress all attachments with the help of one automated solution.

All things considered, it is fairly advisable to protect your outgoing attachments by compressing them into password-protected archives. At the same time, it is handy to have a tool that would do the unpacking of the incoming attachments for you. With Attachments ZIP Compressor, an add-in for Outlook, you can solve both tasks once and for all, as its wide range of flexible settings can optimize even a very heterogeneous flow of attached files from multiple senders and to multiple recipients.

14 thoughts on “Send password-protected attachments in Outlook

  1. Hi, is it possible to create multiple rules with different default passwords?

    For example, lets say I have two different projects: Project Alpha and Project Beta. I want all attachments where the email subject contains the word Alpha to be password protected with the password AAA and all attachments where the email subject contains the word Beta to be password protected with the password BBB.

    Is the above scenario possible? I only see one default password option in the video.

  2. Is it possible to configure sending of the password in a separate email?
    1st email will zip the attachment with a password to recipient A.
    2nd email will be sent to recipient A again with the password to the previous zipped attachment.

    1. Hello, currently there is no such feature available. Thank you for your suggestion.

      1. Hi Nick, thank you for your response. It will be great to join you in your testing. Sure, I can share scenario in our side.

    1. Yes, you can select the sender (for incoming) or recipient (for outgoing) in the “Password Manager” settings – available at the “Archiving” tab in the rule settings.

  3. Hi Marty,

    Because of GDPR, we need to password protect/secure our attachment that content PII data. The emails are auto sent out via SQL Reporting Service (SSRS) using Office365 SMTP. Can you product able to achieve this?

    We have tested Microsoft email encryption function. It works well for us but we found that it doesn’t work for email sending to China email address. The email will be deleted by the Great FireWall in China. But we found that if the attachment is zipped with password, the China email address is able to receive the email.

    Appreciate your early reply

    1. Hello David, thank you for your question.
      Yes, our Compression tool should help you with your task, if your outgoing messages are sent though Outlook while it is running in full mode, and appear in Outbox as well.
      The rule in the ZIP-Compressor component of Attachments Processor for Outlook can automatically archive your attachments in outgoing messages: either for all, or for selected recipients;
      and protect your ZIP-archive with the password as well.
      Please download and test its free trial version.

  4. We have Office 365 for Mac outlook v15.34 We send personalized sensitive data to clients. The documents are created using mail merge and sent each individual client via outlook. Password protecting each attachment is laborious and needs to be automated. Is there a product you have which will allow us to add-in to 365?

    1. Hello Marty, thank you for your question.
      With Attachments Processor, you can configure a rule for archiving attachments in outgoing messages and protecting them with passwords. And such a rule will process in Outlook personal messages created using the Mail Merge feature as well.
      But our add-ins are compatible merely with Windows-based Microsoft Office versions. It will not work for the Mac version, unfortunately.

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