To configure Attachment compliance settings for your domain or organizational unit:
2. From the dashboard, go to Google Apps > Gmail > Advanced settings.
3. Attachment complianceNot configured yetConfigureLocally appliedEditAdd another
4. InboundOutboundInternal - sending—Messages sent by your users to
recipients within the set of domains associated with your company or
Internal - receiving
5. Click Add to
add an expression. (You can add several expressions to one attachment
compliance setting.) For each expression:
Select File type from the drop-down list (displayed by default), and choose the attachment types to include. This expression looks for a match on attachments of specific types; for example, Office documents, Video and multimedia, Music and sound, Images, and Compressed files and archives (both encrypted and not encrypted).
For a list of file extensions that are classified in each file type, see File types and file extensions. (Note: For your protection, all executables are automatically rejected.)
You can also enter Custom file types to look
for matches on specific file extensions; for example, exe, bat, and cmd. Enter
one or more file extensions, without a period, and separate your entries by
commas. Click Save.
Select File name and enter an attachment name that you want to include. This expression looks for a match on any part of an attachment file name; it need not match the entire name. (Case is ignored.) ClickSave.
Select Message size and enter the number of megabytes to limit the size of messages (Ex.5 Mb). Click Save.
above expression matches This section enables you to specify action to be
perform. You have two options in
the drop-down menu: Reject message or Modify message.
Reject message This option rejects the message before it reaches the intended recipient. You can then enter customized text for the rejection notice.