Shared Mailbox: Added support for shared mailboxes in hybrid environments.

August 12, 2025
Version 16.100 (Build 25081015)

Feature updates
Excel

• Compatibility Versions: Compatibility Versions are set per workbook. Version 1 reflects historical calculation behavior while Version 2 contains the improvements to Excel text functions.
• View multiple panes, sheets or workbooks side by side: You can now quickly compare worksheets in the same workbook or in different workbooks by viewing them side by side with synchronous scrolling and reset window positioning, just like in Excel Windows.

Outlook

• Mail: Linked file indicator now appears in the message list for conversations that include file links, making it easier to spot messages with shared content at a glance.
• Auto Reply: Users can now block their calendar when setting an automatic reply.
• Shared Mailbox: Added support for shared mailboxes in hybrid environments.

Office Suite

• Spotlight Search: You can now use Spotlight Search to find your content
• Change content marking default font to Aptos: When a sensitivity label is configured to insert content marks in Office files, the font of these content marks will now be Aptos by default. Admins can configure a different font for content markings using PowerShell.

Security updates
Excel

• CVE-2025-53735
• CVE-2025-53737
• CVE-2025-53739
• CVE-2025-53741
• CVE-2025-53759
  Word
• CVE-2025-53733
• CVE-2025-53736
• CVE-2025-53738
• CVE-2025-53784
  Office Suite
• CVE-2025-53731
• CVE-2025-53740