I love Zorin OS 18 and it's been my primary daily driver for transitioning from Windows, especially with its excellent Windows-like UX and stability. However, I've encountered critical limitations with GNOME 46's Online Accounts integration for Microsoft 365, which prevent full O365 support (email, calendar, contacts).
Current Issues (Zorin OS 18 / GNOME 46)
Microsoft 365 Online Accounts connects but only enables "Files" (OneDrive). Mail, Calendar, and Contacts permissions are requested but not activated in Evolution
IMAP OAuth2 fails consistently: "User is authenticated but not connected" + NAMESPACE errors in both Thunderbird and Evolution
Folder discovery broken: No folders appear for subscription after OAuth2 handshake succeeds
Proof of Concept - Ubuntu 25.10 (GNOME 49)
Tested Ubuntu 25.10 with GNOME 49:
Settings → Online Accounts → Microsoft 365 → Sign In
→ Full permissions granted (Mail + Calendar + Contacts + Files)
→ Evolution auto-configures: Mail, Calendar, Contacts all sync perfectly
→ Zero OAuth2/NAMESPACE errors
Business Impact
As an IT professional managing O365 environments:
Cannot replace Outlook without full Online Accounts support
Blocks Zorin enterprise adoption for Microsoft-centric organizations
Forces fallback to flaky workarounds (PWA)
Request
Backport/update gnome-online-accounts and related libs to GNOME 49 level while maintaining Zorin Appearance/theme stability.
Zorin would be the premier Windows→Linux migration distro with full O365 integration.
Thank you for building the best Windows-like Linux experience!
I'm not sure if this is makeable because it is a Part of the Desktop. So, I wouldn't expect that this specific Piece can be upgraded without affecting a lot of other Stuff - especially because of shared Dependencies or Libraries.
As @Nourpon mentioned, Zorin follows Ubuntu LTS releases, which happen once every two years. That means they're stuck on GNOME 46 until April 2026 when the next Ubuntu LTS comes out. Then it is expected to be GNOME 50 for Ubuntu 26.04 LTS.
The major change to the underlying system will mean a new major release (i.e., Zorin 19). It will probably take several months to complete that because there's a lot of work that has to be done with a new release to create workable extensions, work out bugs, etc. Plus, it seems GNOME is more tightly locking down their DE with every release.
My suggestion would be, if having full MS365 online accounts is critical to your workflow today, then you may just need to run Ubuntu 25.10. It's a good, stable OS. It takes a little getting used to, but with some minor tweaking, you can pretty quickly give it a more Windows-like feel.
Alternatively, Kubuntu 25.10 would give you a Windows-like feel out of the box, but I don't know that KDE Plasma 6.4.5 would have the MS 365 compatibility you're looking for.
another option would be to let windows take care of windows. Are you're able to have a system set up for that purpose only?
my tech job has involved supporting windows for many years now. When I made the jump to Zorin, on my workhorse computer because I couldn't resist the temptation any longer, I installed windows on a refurbished desktop computer for the purpose of dealing with a couple applications.