Microsoft has fastened a identified subject affecting Outlook for Microsoft 365 customers that triggered issues sending emails for these with too many nested folders.
When it first acknowledged the email-sending points in December, the corporate linked them to an older drawback associated to mailboxes with greater than 500 shared folders—a restrict eliminated in 2019. Nonetheless, Redmond now believes the difficulty additionally impacts customers with an analogous variety of folders of their major mailbox.
Microsoft says customers making an attempt to ship emails from the Outlook desktop app might obtain an sudden Non-Supply Report (NDR) with the 0x80040305 error code.
“This issue is like the prior 500 folder limit that the Outlook Team fixed, Lifting the 500 Folder Limit in Outlook,” the corporate mentioned. “That solution targeted shared folders but did not include the scenario occurring in the user’s primary mailbox.”
Affected customers will even be notified that their emails didn’t attain “some or all” recipients, with the NDR message advising them to resend it later or contact their community administrator.
The Outlook Workforce has developed a repair for this drawback, which might be rolled out to the next launch channels later this month or in December:
- Beta Channel: Model 2410 (Construct 18127.15020), anticipated early October 2024
- Present Channel Preview: Model 2410 (Construct 18129.20000), anticipated October 9, 2024
- Present Channel: Model 2410 (Construct 18129.20000), anticipated October 29, 2024
- Month-to-month Enterprise Channel: Model 2410 (Construct 18129.20000), anticipated December 10, 2024
Workaround additionally accessible
Within the meantime, till the affected customers’ software program is fastened, Microsoft offers a brief workaround requiring them to cut back the variety of folders with subfolders to beneath 500, aiming for 450 nested folders.
One other short-term answer to those Outlook email-sending issues is to maintain all mailbox folders collapsed slightly than expanded.
“If you can’t do either of the above, avoid subsequent online actions in Outlook. Such actions include using the buttons for ‘View on Server’ and ‘Click here to view more on Microsoft Exchange,’ or use of ‘Include older results’ when searching,” Microsoft mentioned.
“If you use any of these actions, restart Outlook immediately for best performance.”
Earlier this month, the corporate additionally addressed a bug inflicting Microsoft 365 apps like Outlook, Phrase, Excel, and OneNote to crash whereas typing or spell-checking a textual content.
In August, Microsoft additionally shared short-term workarounds for identified points triggering Gmail sign-in points for traditional Outlook customers and inflicting Outlook to crash after opening.
