NPrinting Pixel Perfect Error After May 2023 > February 2025 update.

[jonip_78]

I noticed today that some PixelPerfect reports fail to generate.

The following error appears in the report log. I also get the same error when I open the report in Designer and try to preview it.

WARN: error during report generation: 18:  The type 'NPrinting.Reporting.ReportingApp.PixelPerfect.Controls.PPChart' exists in both 'c:\Program Files (x86)\NPrinting\Designer\libs\NPrinting.PixelPerfect.dll' and 'c:\Program Files\NPrintingServer\NPrinting\Engine\Qlik.Reporting.Legacy.PixelPerfect.dll' 19:  The type 'NPrinting.Reporting.ReportingApp.PixelPerfect.Controls.PPChart' exists in both 'c:\Program Files (x86)\NPrinting\Designer\libs\NPrinting.PixelPerfect.dll' and 'c:\Program Files\NPrintingServer\NPrinting\Engine\Qlik.Reporting.Legacy.PixelPerfect.dll' 20:  The type 'NPrinting.Reporting.ReportingApp.PixelPerfect.Controls.PPChart' exists in both 'c:\Program Files (x86)\NPrinting\Designer\libs\NPrinting.PixelPerfect.dll' and 'c:\Program Files\NPrintingServer\NPrinting\Engine\Qlik.Reporting.Legacy.PixelPerfect.dll' 21:  The type 'NPrinting.Reporting.ReportingApp.PixelPerfect.Controls.PPChart' exists in both 'c:\Program Files (x86)\NPrinting\Designer\libs\NPrinting.PixelPerfect.dll' and 'c:\Program Files\NPrintingServer\NPrinting\Engine\Qlik.Reporting.Legacy.PixelPerfect.dll'

I uninstalled Designer and then reinstalled it but still the same.

[jonip_78]

I updated to February 2025 SR6 and experienced the same problem.

I then upgraded to May 2026 and encountered the same issue.

Attached are the error messages I get when I try to open the PixelPerfect report in Designer.

Edit: Actually now after the update it does not open the Designer, I see the Designer logo pop up and after awhile it throws these errors.

[jonip_78 · Accepted solution]

At first, I thought something had gone seriously wrong during the upgrade, but it turned out to be a much simpler issue.

Apparently, there were some DLL changes between 2022 and 2025, but the February 2025 upgrade did not remove the old DLL files.

In the following folder:

C:\Program Files (x86)\NPrinting\Designer\libs

I had these files:

* NPrinting.PixelPerfect.dll < 2022
* Qlik.Reporting.Legacy.PixelPerfect.dll < 2026

The `NPrinting.PixelPerfect.dll` file was a leftover from an old version. After I deleted it, everything started working correctly.

To be safe, I also uninstalled NPrinting Designer, deleted the entire Designer folder, and then reinstalled Designer.