Classic Outlook has been accumulating a series of unresolved technical problems, and Microsoft is now publicly tracking multiple simultaneous bugs affecting the desktop client across email sync, server connections, and basic interface behavior.
The most operationally disruptive issue prevents users from creating groups in classic Outlook when Exchange Web Services (EWS) is enabled for the tenant. The client returns a “Can’t connect to the server” error, traced to an AD Graph call for ValidateUnifiedGroupProperties failing with a specific internal error: both AAD and MSGraph clients are reported as null, or AAD Graph is disabled for the API. According to the announcement, the Outlook team is building updated group functionality using REST APIs to resolve this. Until that release arrives, affected users are directed to create and edit groups through the new Outlook client or Outlook Web Access (OWA).
Gmail and Yahoo Sync Failures
A separate bug is generating error codes 0x800CCC0F and 0x80070057 for users synchronizing Gmail and Yahoo accounts in classic Outlook. The condition appears after changing account passwords — the client does not prompt users to sign back in. The report notes that other, still-unidentified circumstances may trigger the same errors.
The team has not yet identified the root cause. In the meantime, the advised workaround requires users to delete registry entries for the affected email address under the Identities key at Computer\HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\Common\Identity\Identities in the Windows Registry Editor.
That’s a manual, technically involved step — one that average users may find difficult without IT support.
Disappearing Mouse Pointer
A third issue, acknowledged nearly two months after initial user reports, causes the mouse pointer to vanish inside classic Outlook. The same behavior has been observed in OneNote and other Microsoft 365 applications. Microsoft has asked affected customers to open a support case through their Microsoft 365 admin and submit diagnostic log files.
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Three temporary workarounds are available: clicking an email in the message list when the cursor disappears, switching to PowerPoint and clicking into an editable area before returning to Outlook, or restarting the affected computer. All three are described as temporary measures only.
These issues follow a pattern of recent instability in the classic client. In January, Microsoft resolved a separate problem caused by December 2025 updates that had blocked Microsoft 365 customers from opening encrypted emails entirely.
For the cursor and sync bugs, the company says it will share more details once fixes are available. No release timeline has been confirmed for any of the three active investigations.
Photo by Ed Hardie on Unsplash
This article is a curated summary based on third-party sources. Source: Read the original article
