Hi Maxine,
By default, .bat files will be blocked by Outlook for security concern. If you're using Microsoft Exchange Server, typically only the email server administrator can unblock these file types.
If you want the users to receive the blocked .bat files, it is recommended to make the file available without using Outlook, save the file to the cloud, or make it less likely to be blocked by Outlook.
The following are some safe ways to share files with people that you trust:
1. Use a shared server or the cloud
Save the attachment to the cloud, a server, or an FTP site that you can access. This can include OneDrive or a secure network share server such as SharePoint. You can send a link to the attachment on the server or FTP site so that the users can click
the link to access the file and save it to the computer.
2. Use a file compression utility
Using a compression utility, such as WinZip, creates a compressed archive file that has a different file name extension. Outlook doesn’t recognize these file name extensions as potential threats. Therefore, it doesn’t block the new attachment. Many third-party
compression utilities are available.
3. Rename the file
You can rename the .bat attachment to use a file name extension that Outlook doesn’t recognize as a threat.
For more information, hopefully the article below can be helpful:
Blocked attachments in Outlook
Best regards,
Yuki Sun
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