Microsoft is currently investigating a serious service issue preventing customers from downloading Microsoft 365 desktop applications directly from the service homepage. The company has tagged the problem as an “Incident,” which means it’s a critical service issue with noticeable user impact.
The root cause stems from a recent service update. Microsoft’s analysis of its infrastructure components revealed that a code issue within that update is actively impacting the license check process. Essentially, when you try to download the core desktop apps, the system fails to properly verify your paid license, blocking the download entirely.
This is awful for anybody trying to set up a new machine or reinstall their software quickly. You’ve paid for the subscription, but you can’t get the primary tools you need, which is a big deal. Extended downtime on core functionality like this can be a violation of some terms and conditions.
The incident, identified by ID OP1192004, was formally logged on December 2, 2025. Microsoft confirmed that any user attempting to download the Microsoft 365 desktop apps from the homepage may be affected by this event. Fortunately, Microsoft has already developed a fix for the problem. The teams are currently validating and testing this fix in their internal environment to ensure its efficacy before deploying it to the affected infrastructure.
There is no estimated deployment timeline, but hopefully, this deployment is quick because having paying customers unable to access core downloads is a bad look for a major enterprise service. The company is dealing with more than one issue right now, though. Alongside the download issue, Microsoft is also working to resolve a known bug affecting the new Outlook client.
This separate issue is keeping some users from opening Excel email attachments. The underlying cause here is an encoding error in Excel file names. If the file name contains non-ASCII characters, the user sees a “Try opening the file again later” error message. This is a classic example of how minor encoding hiccups can completely derail your workflow, especially if you deal with international file names.
Microsoft noted that this Excel issue may affect any user who attempts to open attachments with those specific non-ASCII characters in the name. However, the company labeled this issue as an “Advisory,” which suggests it has a more limited scope or impact compared to the critical license check incident.
Microsoft has already deployed a fix to address the missing encoding in the requests used to open these files. While that fix is still being validated and hasn’t reached all affected customers yet, there’s a simple workaround. If you’re running into issues opening those Excel attachments, you can temporarily switch to using Outlook on the web.
Alternatively, you can download the file to your local system and open the document there. This lets users bypass the specific encoding failure within the new Outlook client itself.
Clearly, there are some issues that need to be fixed. Given the critical nature of the current download block, I would expect Microsoft to push out that tested fix very soon.
Source: Bleeping Computer
