Calman users may find that PDF export for calibration reports fails after installing a recent Windows update for .NET Framework. This issue is currently under investigation.
Issue: After installing the August 11, 2026 .NET Framework cumulative update, PDF export for calibration reports fails. The export dialog behaves normally, but no PDF file is written to the destination folder. This affects Calman broadly and is not limited to a specific version. A permanent fix is in progress; in the meantime, uninstalling the update resolves the issue.
How to tell if you’re affected
- Export a calibration report to PDF as usual.
- Check the destination folder you selected. If no PDF file appears and no error was shown, you are affected.
- This issue affects older versions of Calman, not just the current release.
A fix will be included in an upcoming Calman update, available only to users with current maintenance:
- An active Calman All-Access membership
- A license still within its initial one-year update period.
Older, unmaintained versions of Calman will not be patched. If your maintenance is not current, use the Windows-side workaround below instead.
Affected update
Microsoft released this fix across all supported Windows versions on August 11, 2026, under different KB numbers per OS version:
| Windows version | KB number |
| Windows 11, version 25H2 / Server 24H2 | KB5120708 |
| Windows 11, version 24H2 | KB5120710 |
| Windows 10, version 22H2 | KB5121647 |
| Windows 10, version 21H2 | KB5121646 |
| Windows 10, version 1809 / Server 2019 | KB5121645 |
If your KB number isn’t listed above, check Windows Update history for a “.NET Framework” cumulative update installed on or shortly after August 11, 2026, and use that entry instead.
Workaround: uninstall the update
Uninstalling the update restores PDF export. This is a security update, so treat this as a temporary measure and reinstall it once Calman releases a permanent fix.
- Open Update history.
- Windows 11: click Start, open Settings, go to Windows Update > Update history.
- Windows 10: click Start, open Settings, go to Update & Security > Windows Update > View update history.
- Open the uninstall menu.
- Click Uninstall updates (Windows 11) or Uninstall updates at the top of the history page (Windows 10).
- Locate and remove the update.
- Find the KB number matching your Windows version from the table above.
- Click Uninstall next to the entry and confirm.
- Restart the computer.
- A restart is required for the change to take effect.
- Pause updates to prevent reinstallation.
- In Windows Update settings, click Pause updates and select a duration.
- This prevents Windows from automatically reinstalling the update before a permanent fix is available.
Portrait Displays is working on a permanent fix. This article will be updated when one is available.