Microsoft exchange attachment size

The following articles describe how to compress and extract files for different Windows operating systems. Windows Zip and unzip files. Windows 8. Windows 7: Compress and uncompress files zip files. Under the Image Attachments section, select Resize large images when I send this message. Note: For more information on how to change maximum allowable attachment sizes, see "Attachment size exceeds the allowable limit" error. To help reduce the size of attachments that you send in Outlook, see Reduce the size of pictures and attachments.

In addition to mail provider limits on total message size, sending large attachments through email is not always the best solution. Your message might cause your mailbox to exceed the storage quota Each message that you send is saved in the Sent Items folder. Sending large attachments to other people counts against your mailbox size quota as well. When you exceed the storage quota, you could be blocked from receiving additional messages. Attachment bloat When a file is attached to message, it has to be encoded.

The encoding process causes attached files to become 1. For example, if you send a 5 MB file attachment, the attachment is sent as 6. There are several ways to share large files and collaborate with other people without sending attachments. For more information, see Save a file to a SharePoint library. SharePoint libraries can be accessed directly in Outlook. This attachment limit is not related to the limit in Outlook for Internet email accounts.

This limit for an Exchange mailbox stems from the Maximum send size setting that is configured in the Transport Settings Properties dialog box by the Exchange administrator Refer the following screen shot. The steps to modify the default attachment limit depend on the type of email account that you are using with Outlook. Important This article contains information about how to modify the registry. Make sure that you back up the registry before you modify it. Make sure that you know how to restore the registry if a problem occurs.

For more information about how to back up, restore, and modify the registry, click the following article number to view the article in the Microsoft Knowledge Base: How to back up and restore the registry in Windows XP and Windows Vista. To modify the default attachment limit size in Outlook for an Internet email account yourself, follow these steps:.

The x. Value data: An integer that specifies the total maximum allowable attachment size. For example, specify Decimal to configure a MB limit. Specify a value that is less than 20 MB if you want to configure a limit that is less than the default 20 MB. If you are using an Exchange Server account, the MB attachment limit for Internet email accounts is not used by Outlook.

Instead, Outlook uses the limit that is configured on your Exchange server. For example, IT administrators can't create shared mailboxes and have users copy through the Cc or Bcc field, or through a transport rule a shared mailbox for the explicit purpose of archiving. To increase the mailbox size, an Exchange Online Plan 2 license must to be assigned. Exchange Online provides three kinds of notifications when a user's mailbox is nearing, or at, capacity:.

Warning : The user receives an email warning that the mailbox is approaching the maximum size limit. This warning is intended to encourage users to delete unwanted mail. Prohibit Send : The user receives a prohibit-send notification email when the mailbox size limit is reached. The user can't send new messages until enough email is deleted to bring the mailbox below the size limit. The sender has the option to try resending the mail later.

To receive messages again, the user must delete email until the mailbox is below the size limit. These limits are intended to limit mailboxes to known dimensions that can be supported in Exchange Online.

The goal of these limits is to prevent an infinite number of mailbox items per folder, an infinite number of folders per mailbox, or an infinite number of public folders per Exchange Online organization. For practical purposes, mailbox folder limits are in effect unlimited and sufficient to support most Exchange Online mailboxes and on-premises mailboxes that are migrated to Exchange Online.

Maximum number of messages per mailbox folder : Specifies the maximum number of messages for a mailbox folder. New messages can't be delivered or saved in a folder when this limit is reached.

Warning for number of messages per mailbox folder : Specifies the number of messages that a mailbox folder can hold before Exchange Online sends a warning message to the mailbox owner. When this quota is reached, warning messages are sent once a day. Maximum number of messages per folder in the Recoverable Items folder : Specifies the maximum number of messages that can be contained in each folder in the Recoverable Items folder.

When a folder exceeds this limit, it can't store new messages. For example, if the Deletions folder in the Recoverable Items folder has exceeded the message count limit and the mailbox owner attempts to permanently delete items from their mailbox, the deletion will fail.

Warning for number of messages per folder in the Recoverable Items folder : Specifies the number of messages that each folder in the Recoverable Items folder can hold before Exchange Online logs an event to the application event log. Maximum number of subfolders per mailbox folder : Specifies the maximum number of subfolders that can be created in a mailbox folder.

The mailbox owner won't be able to create a new subfolder when this limit is reached. Warning for number of subfolders per mailbox folder : Specifies the number of subfolders that can be created in a mailbox folder before Exchange Online sends a warning message to the mailbox owner. Maximum folder hierarchy depth : Specifies the maximum number of levels in the folder hierarchy of a mailbox. The mailbox owner won't be able to create another level in the folder hierarchy of the mailbox folder when this limit is reached.

Warning for folder hierarchy depth : Specifies the number of levels in the folder hierarchy of a mailbox folder that can be created before Exchange Online sends a warning message to the mailbox owner. Maximum number of public folders : Specifies the maximum number of public folders in the complete public folder hierarchy. When this limit is reached, existing public folders must be deleted before new public folders can be created. Maximum number of subfolders per public folder : Specifies the maximum number of subfolders that can be created in a public folder.

New subfolders can't be created in a public folder when this limit is reached. Warning for number of subfolders per public folder : Specifies the number of subfolders that can be created in a public folder before Exchange Online sends a warning message to the folder owner.

If no owner exists, warning messages are sent to users with Owner permissions. The storage quota for the archive mailbox is 1. For information about increasing the Recoverable Items quota, see Increase the Recoverable Items quota for mailboxes on hold.

When auto-expanding archiving is turned on, additional storage is automatically added when the storage capacity for the Recoverable Items folder is reached. See the Microsoft Roadmap for details about availability of auto-expanding archiving. There can be only 10, direct child folders for any given parent. This applies regardless of migration or other clients creating folders. Message size limit : Message size limits are necessary to prevent large messages from blocking delivery of other messages and affecting service performance for all users.

These limits include attachments, and apply organization-wide to all messages inbound, outbound, and internal. Messages larger than this limit will not be delivered, and the sender will receive a non-delivery report NDR. While message size limits can be configured up, down, or on a per-user basis, administrators can also create transport rules to limit the maximum size of any individual attachment.

To learn more, see Microsoft supports larger email messages. Some email clients may have lower message size limits or may limit the size of an individual file attachment to a value that is less than the Exchange Online message size limit. Message header size limit : Specifies the maximum size of all message header fields in a message. The current limit is KB. If the total size of all message headers exceeds KB, Exchange Online will reject the message with error " 5.

Because the header fields are plain text, the size of the header is determined by the number of characters in each header field and by the total number of header fields. Each text character consumes 1 byte. Subject length limit : The maximum number of text characters allowed in the subject line of an email message.

File attachments limit : The maximum number of file attachments allowed in an email message. Even if the total size of all the file attachments doesn't violate the message size limit, there is still a limit on how many attachments are allowed in the message.

This limit is controlled by the multipart message limit. This is the maximum file size of a single attachment. Individual client programs, including Outlook on the web, may limit the size of attachments below this maximum. Exchange ActiveSync does not implement attachment size limits on an individual attachment basis. The total size of all attachments to an Exchange ActiveSync message must be less than the message size limit.

Multipart message limit : The maximum number of message body parts that are allowed in a MIME multipart message. This limit also controls the maximum number of file attachments that are allowed in a message. Embedded message depth limit : The maximum number of forwarded email messages that are allowed in an email message.

You can follow the question or vote as helpful, but you cannot reply to this thread. I have the same question Report abuse. Details required :. Cancel Submit. Hi Questor, We can upgrade the message size limit for larger attachments.