Attachments supports attachments in e-mails. To protect you from attacks and SPAM there are however a number of restraints in place. You can loosen or tighten these restrictions according to your needs on the configuration page (see Getting Started) in the Attachments tab.

Shows where to find the Attachment Tab in the Add-on settings.

Attachment Size & Number of Attachments Limits

You can limit the maximum number of attachments per e-mail and the maximum size of every attachment. Attachments that do not comply with these rules are dropped and are not added to Confluence. The default settings should be fine for most users.

Most mail providers have restrictions regarding attachment sizes. For example, you cannot send e-mails that are larger than 30MB in size (content & all attachments in total). All attachments also need to be smaller than the general maximum attachment size set in Confluence. You can check your general maximum attachment size by going to Settings in the navigation panel, General Configuration and then going to the Attachment Settings section. The default general attachment limit is 100MB.

There are no platform limitations regarding the number of attachments. The default value after installation is -1 which means no restrictions. You're able to put in any positive integer if you want to restrict the number of attachments. To disable all attachments simply set the maximum number of attachments to 0.

Shows the first two attachment settings: size and number.

File Types

Some attachments in e-mails may contain viruses. Therefore, all attachments are scanned by antivirus. However, there is no such thing as a 100% detection rate. This is why only file types that are considered safe are allowed by default. Windows uses file extensions to categorize files, the web uses mime types. To prevent bypassing of filters it is important that file extensions and mime types are checked and match. You can edit the list of allowed file extensions/mime types to allow additional file types or to enforce more restrictions.

Allowing new file types

If you want to allow a new file type as attachment you need to do 4 steps:

  1. Click the Add File Type Button at the bottom of the Page.
  2. Insert the Mime Type in the respecting field.
  3. Insert the File Extension in the respecting field. Leading dots are ignored.
  4. Click Save Settings

Shows the four steps you need to do to allow a new file type as attachment.

If you do not know the mime type of the files you want to allow you can visit the following link to search for it: Mime types

Disallowing file types

To disallow a file type simply delete it from the List. Click on the little trash can icon next to the rule and then click on Save Settings

Shows how to delete a whitelist rule for a file type.


Congratulations, now you know how to manage your Attachments.