Office 2021 and Windows 11 24H2 support ended: what to check
Yesterday, 13 October 2026, Microsoft ended support for Office 2021 and for Windows 11 version 24H2 on Home and Pro editions. Nothing will stop working this morning, but the PCs and apps involved no longer get security fixes. For a small business, that quietly turns everyday tools into a weak spot.
What changed
Microsoft's own end-of-support page for Office 2021 is clear: the apps "may continue to function", but Microsoft "will no longer provide technical support, bug fixes, or security fixes". It warns that continuing to use them could expose you to "serious and potentially harmful security risks".
According to Office Watch, this covers both the retail versions (Office Home & Business 2021 and individual apps such as Word, Excel, Outlook and Publisher 2021, on Windows and Mac) and the volume-licence Office LTSC 2021 editions, including Project and Visio 2021.
On the Windows side, BleepingComputer reports that Windows 11 version 24H2 Home and Pro stopped receiving monthly security updates on the same date. Enterprise and Education editions of 24H2 remain supported until October 2027. Microsoft's recommended path is Windows 11 version 25H2, which installs over 24H2 as a small update rather than a full reinstall.
Office Watch also notes two related changes for Microsoft 365 subscribers: Microsoft 365 Apps on Windows 10 are now frozen at Version 2608 and will get security updates only (until October 2028), and Publisher stopped working for Microsoft 365 subscribers on 1 October.
Why it matters for your business
Most attacks on small businesses don't need anything clever. They rely on known, already-patched flaws in software that hasn't been updated. An unsupported copy of Outlook or Word opening attachments all day, or a laptop that has stopped receiving Windows patches, is exactly the kind of gap criminals look for. It can also become a talking point with your cyber insurer or auditor, and POPIA expects you to take reasonable security measures to protect personal information.
What to do this week
- Check your Office version. In Word or Excel, go to File > Account. If it says Office 2021 or Office LTSC 2021, that machine is now unsupported. If it says Microsoft 365, you are on the subscription and still receiving updates.
- Check your Windows version. Press the Windows key, type winver and press Enter. If you see "Version 24H2" on Home or Pro, go to Settings > Windows Update and choose Check for updates. Eligible PCs should offer "Download and install Windows 11, version 25H2". BleepingComputer reports that unmanaged Home and Pro PCs will be moved across automatically, but managed business devices are not, so don't assume it has happened.
- Make a simple list. Note each PC, its user, its Windows version and its Office version. Ten minutes with a spreadsheet tells you exactly where your exposure is.
- Decide on Office. Your options are moving those users onto a Microsoft 365 business plan (which keeps Office current automatically) or buying a newer standalone version. Weigh it against how you already handle email, file sharing and backups.
- Look for Publisher files. If anyone still relies on .pub files, open and convert them to Word or PDF on a machine that can still run Publisher, before you lose access.
- Keep Windows 10 in view. If you still have Windows 10 PCs running Microsoft 365, their apps are now on a security-only track. Plan their replacement or upgrade rather than leaving them indefinitely.
No need to panic
An unsupported PC is not a breached PC. But the longer it runs without fixes, the bigger the risk becomes. A short audit now, followed by a planned upgrade, is far cheaper and less disruptive than cleaning up after an incident.
Not sure which of your PCs are affected? Orlik IT can audit your Windows and Office versions, plan the upgrades and handle the move to Microsoft 365 with minimal disruption to your team. Get in touch and we'll help you get it sorted.