When creating an Office 365 backup, attachments are often just as important as the email messages themselves. A backup that contains only the message text may not be useful if users later need the original documents, images, or other files attached to those emails.

A practical approach is to use a backup tool that lets you decide whether attachments should be included. SysInfo Office 365 Backup Tool allows users to save mailbox emails with or without attachments, depending on their backup requirements. It can also save Office 365 data locally in formats such as PST, MBOX, PDF, EML, MSG, and CSV.

Before starting the backup, users can preview the mailbox in a tree-style structure and select the folders they need. This is useful when only certain mailboxes or folders need to be archived rather than creating a complete backup every time. Date filtering is also available for selecting data from a particular period.

For larger mailboxes, I would first decide whether attachments are required for the archive, then select the relevant folders and apply a date range if necessary. The resulting backup can be saved to a separate local location for future access.

This approach gives more control over backup size while still allowing important email content and attachments to be preserved when they are required.