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Changing how the BlackBerry Messaging Agent reconciles attachments to the messaging server

The BlackBerry® Messaging Agent receives message attachments from supported BlackBerry devices and reconciles the attachments to the messaging server. The BlackBerry Attachment Service does not convert the attachments.

The entries in the CMIME service book on BlackBerry devices indicate whether the BlackBerry® Enterprise Server Express supports attachments that users send from their BlackBerry devices. Users must have BlackBerry® Desktop Software version 4.2 or later installed on their computers to make sure that these service book entries remain on their BlackBerry devices during service book updates over a physical connection to a computer that is running the BlackBerry Desktop Software.

By default, the BlackBerry Messaging Agent limits the file size of attachments that it can receive from a BlackBerry device to a maximum of 3 MB. If the BlackBerry Messaging Agent receives more than one attachment at a time, it limits the total file size of all of the attachments to a maximum of 5 MB.

Data that a BlackBerry device and the messaging server send each other over the wireless network must be in packets that are no larger than 64 KB. If a BlackBerry device sends an attachment that is larger than a single packet, the BlackBerry device divides the attachment into multiple packets. The BlackBerry Messaging Agent caches all of the packets and sends the attachment to the messaging server after it receives the last packet.

You can optimize the amount of memory and the number of transactions that the BlackBerry Messaging Agent uses when it receives attachments by changing the maximum file size of attachments or preventing users from sending large attachments.

Users with BlackBerry devices that are running BlackBerry® Device Software version 4.5 or later can download attachments in any native format to their BlackBerry devices. Users can open and make changes to native file formats using an appropriate third-party application on their BlackBerry devices. Users might be able to open specific file formats using the media application on their BlackBerry devices.

To manage network resources in your organization's environment, you can change the maximum file size of attachments that users can download to their BlackBerry devices.

Change the maximum file size for attachments that users can send

By default, the maximum file size of a single attachment that users can send is 3072 KB, and the maximum file size of multiple attachments that BlackBerry® devices can send in a single email message is 5120 KB.
  1. In the BlackBerry Administration Service, on the Servers and components menu, expand BlackBerry Solution topology > BlackBerry Domain > Component view > Email.
  2. Click the instance that you want to change.
  3. Click Edit instance.
  4. On the Messaging tab, in the Messaging options section, perform any of the following actions:
    • To change the maximum file size for a single attachment that BlackBerry devices can send, in the Maximum single attachment upload size (KB) field, type a number that is between 1 and 3072 KB.
    • To change the maximum file size of multiple attachments that BlackBerry devices can send at one time, in the Maximum multiple attachment upload size (KB) field, type a number that is between 1 and 5120 KB that is greater than the value in the Maximum single attachment upload size (KB) field.
  5. Click Save all.

Prevent users from sending large attachments

If you prevent users from sending large attachments, they can only send specific attachments, such as certificates and contact list entries, that are less than a single packet.
  1. In the BlackBerry® Administration Service, on the Servers and components menu, expand BlackBerry Solution topology > BlackBerry Domain > Component view > Email.
  2. Click the instance that you want to change.
  3. Click Edit instance.
  4. On the Messaging tab, in the Messaging options section, in the Maximum single attachment upload size (KB) field, type 0.
  5. Click Save all.

Change the maximum file size of attachments that users can download

On BlackBerry® devices that are running specific versions of the BlackBerry® Device Software, users can download attachments in native formats (for example, .txt for a text file) to their BlackBerry devices. Users can open and make changes to the files that they download using an appropriate third-party application on their BlackBerry devices. A user might be able to open specific file formats using the media application on the BlackBerry device.

The default maximum file size of attachments that users can download to their BlackBerry devices is 3072 KB (3 MB).

  1. In the BlackBerry Administration Service, on the Servers and components menu, expand BlackBerry Solution topology > BlackBerry Domain > Component view > Email.
  2. Click the instance that you want to change.
  3. Click Edit instance.
  4. On the Messaging tab, in the Messaging options section, in the Maximum single attachment download size (KB) field, type a number, in KB, that is between 0 and 10240 (10 MB). If you type 0, users cannot download attachments in a native format to their BlackBerry devices.
  5. Click Save all.

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