Microsoft released security updates for .Net on August 11 to address six unique vulnerabilities. After installing the update on supported systems, users may notice printing issues.
Microsoft confirmed the issue in the release notes for the update. There, the company notes that “some WPF applications may fail with a System.IO.FileFormatException when printing or generating PDF/XPS content that uses certain fonts, including Calibri” after installing the update.
WPS refers to Windows Presentation Foundation, “UI framework that’s resolution-independent and uses a vector-based rendering engine, built to take advantage of modern graphics hardware.”
The issue is under investigation currently and there is no workaround for users at the time. App developers, who use WPF, may make use of a workaround to mitigate the issue.
Doing so will “disable security productions introduced in the August 2026 update”, which may increase the exposure to the addressed vulnerabilities.
Uninstalling the update could also restore printing functionality, but I have not tested this as I could not replicate the issue on my devices. Considering that disabling the security fixes is a recommended workaround by Microsoft, I’d say there is a good chance that this could work.
Printers are already difficult to get working in windows as it is thanks to lazy and greedy companies that are colluding with operating systems to depreciate your printer so you will just buy a new one year upon year.
Shithouse companies like canon that often release products without drivers at all and are at the mercy of some generic trashed from windows either on the windows store or depend on it being inbuilt both of which are halfhearted trash that does not produce the results you expect or meet the printers needs.
100% sure someone is going to recommend Brother here at some point too for some reason.
Let’s just summaries this article with another day, another Microsoft fudge up.
We can also state that printer companies are all trash these days too with only one or two examples of specific printers that aren’t the rest are just sidewalk trash waiting to be picked up on the next trash day.