Attachment size exceeds the allowable limit" error when you add a large attachment to an email message in Outlook 2010

Internet email account (POP3, IMAP, HTTP)

To modify the default attachment limit size in Outlook 2010 for an Internet email account, follow these steps:

1. Exit Outlook.
2. Start Registry Editor.
3. Locate and then select one of the following registry subkeys:
   
   
   HKEY_CURRENT_USER\Software\Microsoft\Office\14.0\Outlook\Preferences
   HKEY_CURRENT_USER\Software\Policies\Microsoft\Office\14.0\Outlook\Preferences
   
   
   Note Manually create the path in the registry if it does not currently exist.
4. Add the following registry data under this subkey:
   
   
   Value type: DWORD
   Value name: MaximumAttachmentSize
   Value data: An integer that specifies the total maximum allowable attachment size. For example, specify 30720 (Decimal) to configure a 30-MB limit.
   Notes
   • Specify a value of zero (0) if you want to configure no limit for attachments.
   • Specify a value that is less than 20 MB if you want to configure a limit that is less than the default 20 MB.
5. Exit Registry Editor
6. Start Outlook.

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