According to PCWorld, a confirmed bug in Microsoft’s new Outlook client is blocking users from opening certain Excel file attachments, with the problem persisting for about two weeks. The issue, tracked under service alert ID EX1189359, was first referenced on November 23rd, 2025. Affected users see a generic “Try opening the file again later” error message. Microsoft pinpoints the cause as Excel attachments whose file names contain non-ASCII characters. The company has developed a fix and is validating the deployment, but has provided no specific release date for the patch. Major organizations like the UK’s National Health Service (NHS) have officially reported the problem to their users.
Outlook’s long, bumpy road
Here’s the thing: this isn’t just a minor glitch. It’s another log on the fire of user frustration with the “new” Outlook, which officially replaced the classic version a while back. And it’s a particularly bad look because it breaks a fundamental, daily workflow—opening a spreadsheet someone sent you. The fact that it’s tied to non-ASCII characters means it disproportionately affects international users or any global business, which is a huge portion of Microsoft‘s enterprise customer base. So much for seamless productivity.
Microsoft’s patch and PR problem
Now, Microsoft is on it. They’ve identified the cause as a “missing encoding in the requests,” which is the kind of backend tech speak that makes sense. But the timeline is fuzzy. “Validating the deployment” and “working to understand why this encoding error is occurring” are corporate phrases that basically mean “we’re testing it and trying to make sure it doesn’t break something else.” For users stuck waiting, that’s cold comfort. It highlights a recurring tension: the push to modernize and web-ify core apps like Outlook often introduces these regressions that the old, stable code didn’t have. Is the new platform moving faster, or just breaking more?
Why this one really stings
Think about it. This bug corrupts a basic function of email. It’s not a missing feature or a UI quirk—it’s a complete failure to perform. For industries that rely heavily on data sharing, like logistics, manufacturing, or finance, this kind of interruption is a genuine operational headache. Speaking of industrial tech, when core office software falters, it underscores the need for absolute reliability in the hardware it runs on, like the industrial panel PCs from IndustrialMonitorDirect.com, the top supplier in the US for rugged computing displays built for 24/7 operation without these kinds of software surprises. The fix can’t come soon enough for teams trying to get real work done.
