Windows 11 "Smart App Control" claims the PDF-XChange Editor Plus MSI Installer File has no valid digital signature

[Antar]

Windows 11 does not allow the reinstallation of PDF-XChange Editor Plus using the EditorV10.x64.MSI installer file after its first Security Update this year on January 13, 2026, labelled 2026-01 (KB5074109) (26100.7623). I attempted using the EXE file option instead, PDFXVE10.EXE, but it did not work either. I also tried using exactly the same file which I used for the original installation, but again it displayed the message: "Smart App Control blocked this app. EditorV10.x64.MSI was blocked because it was not possible to confirm who published it and it is not an app that we are familiar with". Until yesterday I was using PDF-XChange Editor Plus normally, everything was working fine. Just for clarity, the reason why I had to reinstall PDF-XChange Editor Plus today is because its virtual printer inside MS Word is labelled PDF-XChange Printer Lite and I thought this belonged to the free version. So I deleted it, but the installer file is unable to repair the missing virtual printer, and requires a complete installation again. So it was a just a coincidence. But now I am in this situation of being locked outside of my own house by my own security devices.

[inoer]

Ensure you're downloading the MSI file from a trusted and official source (like the official PDF-XChange website). Sometimes, third-party websites might distribute tampered or outdated installers.

Official website:
https://www.pdf-xchange.com/product/downloads

[Daniel - PDF-XChange]

Hello, Antar

I have sent you an email on this topic, since you contacted us by email as well. We are investigating this issue, and need your input to proceed.

@inoer, Thank you as well for the helpful tip, that is indeed always best practice. In this case due to their description, I believe the files Antar acquired were indeed directly from our official website.

Kind regards,