IronPDF on Windows Server Core Containers

Solution

Add the font to the system fonts directory and register it so the renderer can find it. The Dockerfile below copies arial.ttf into place and writes the matching registry entry:

FROM mcr.microsoft.com/dotnet/sdk:8.0-windowsservercore-ltsc2022 as base
USER ContainerAdministrator
WORKDIR C:/

COPY arial.ttf c:/windows/fonts/arial.ttf
RUN powershell.exe -NoProfile -Command New-ItemProperty -Path 'HKLM:\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Fonts' -Name 'Arial (TrueType)' -PropertyType String -Value arial.ttf

Each line earns its place:

• USER ContainerAdministrator: grants the permission needed to modify the system registry and install fonts.
• COPY arial.ttf c:/windows/fonts/arial.ttf: places the Arial font file into the system fonts directory.
• New-ItemProperty: registers Arial so the system recognizes it and can use it during PDF rendering.

Repeat the COPY and RUN pair for any other typeface your documents rely on.