Convert PDF to DOCX using Aspose.PDF for .NET under Linux - object reference not set to an instance

Aspose.PDF Product Family
1

new Aspose.Pdf.Document(pdfFileLocation).Save(wordFileLocation, SaveFormat.DocX)

Throw the error:
System.NullReferenceException: Object reference not set to an instance of an object.
at #=zD0fa8itO5ui54F8jEYXzphgyuYHPVRG_hCUT$NzZJbO9.#=zmbjyF2HNTn7b()
at #=zBpwQv4kqNuLWVhg1HEhtn9uKgk50SQVg8ibOS_1i0Rbf7zgsFw==.#=zfBd9dI8=(#=z7GS$1utcjEvFgZ_8ESrPzhah2f1y8rftmfe8ck9Z$OQQ #=z4aTy0Hc=, #=zYoQVCAbCU4j9kycH3YDuII1uroSbBk1Avr5QKdPE_bEb #=zvYmSv1E9vNaB, #=zCvqUyy58DIav7tcWZlxGEoxFDr$V$7fSyg== #=z3hfAmLg=)
at #=zELMwkqufAmt6AlqpGYl3U3zLFyyrFR7eSUdtN6GdAMw1DfVJqg==.#=zfBd9dI8=(#=z7GS$1utcjEvFgZ_8ESrPzhah2f1y8rftmfe8ck9Z$OQQ #=z4aTy0Hc=, #=zYoQVCAbCU4j9kycH3YDuII1uroSbBk1Avr5QKdPE_bEb #=zvYmSv1E9vNaB)
at #=z3NJn0rgKZdfKwcCHUdmeHE0XVh$4zz08yIBhmVTy6SjU.#=zFb8P2o_Evu2KQ8cQSg==(#=z7GS$1utcjEvFgZ_8ESrPzhah2f1y8rftmfe8ck9Z$OQQ #=z4aTy0Hc=, List1 #=zmTg3oAs=) at #=z3NJn0rgKZdfKwcCHUdmeHE0XVh$4zz08yIBhmVTy6SjU.#=zeESHUxaS$kzduBGUxg==(#=z7GS$1utcjEvFgZ_8ESrPzhah2f1y8rftmfe8ck9Z$OQQ #=z4aTy0Hc=, List1 #=zmTg3oAs=)
at #=z3NJn0rgKZdfKwcCHUdmeHE0XVh$4zz08yIBhmVTy6SjU.#=zjYxDj1s5O5FL(#=z7GS$1utcjEvFgZ_8ESrPzhah2f1y8rftmfe8ck9Z$OQQ #=z4aTy0Hc=, List1 #=zWOmyDDdha8_I) at #=z3NJn0rgKZdfKwcCHUdmeHE0XVh$4zz08yIBhmVTy6SjU.#=zl9_56XU=(#=z7YJ6FD11yomS8Ad5MwdRkHNkTuLn #=z0swRsQA=, #=zFXLkxeb0R0MZuadF9qn0WcJexYO00eQvNw== #=zn9Zfcj8=, #=z7GS$1utcjEvFgZ_8ESrPzhah2f1y8rftmfe8ck9Z$OQQ #=z4aTy0Hc=) at #=zKOVyNvh3VYYIok2dtAjosGZKA7fKYXdWoA==.#=zaIrs9JQ=(Int32 #=zN2fFN_8=, IList1 #=zsnRIwefLoit3OCJLhA==, #=zmPj8OCpJ9ntK #=zcYdIMgs=)
at #=zKOVyNvh3VYYIok2dtAjosGZKA7fKYXdWoA==.#=zl9_56XU=()
at #=zqL8JMLHlm1qm2zxInq2O8Y90A0It.#=zee4Tgs8XLffv(Document #=z0swRsQA=, #=z7GS$1utcjEvFgZ_8ESrPzhah2f1y8rftmfe8ck9Z$OQQ& #=zZInXOfthePmjwOb43w==, UnifiedSaveOptions #=zkPLPQeA=, Int32& #=zmnMNLxA0xTnX, Boolean #=zoawTHck=)
at #=zqL8JMLHlm1qm2zxInq2O8Y90A0It.#=zdjbsrSYCPe0$x1AICA==(Document #=zXOj1L9eX9YMl, #=z7GS$1utcjEvFgZ_8ESrPzhah2f1y8rftmfe8ck9Z$OQQ& #=z4aTy0Hc=, UnifiedSaveOptions #=zkPLPQeA=, Int32& #=zVqfNwsZ1NfaD, Boolean #=zoawTHck=)
at #=z1uk1kmFz4$dZYJUlaqR3HH4=.#=zdY03P4A=(Document #=z0swRsQA=, Stream #=zEIpCJDiFv3dI, DocSaveOptions #=zkPLPQeA=)
at Aspose.Pdf.Document.#=z4hZe98z$mC5e(Stream #=zEIpCJDiFv3dI, SaveOptions #=zkPLPQeA=)
at Aspose.Pdf.Document.#=z4hZe98z$mC5e(String #=zrrBoMbipHx43, SaveFormat #=z67h4_4U=)
at Aspose.Pdf.Document.Save(String outputFileName, SaveFormat format)

2

@samuelkdavis

Would you kindly make sure that following packages and installations are made to the environment in which you are using the API:

  1. libgdiplus package
  2. package with Microsoft compatible fonts: ttf-mscorefonts-installer. (e.g. sudo apt-get install ttf-mscorefonts-installer )

These fonts should be placed in “/usr/share/fonts/truetype/msttcorefonts” directory as Aspose.PDF for .NET scans this folder on Linux like operating systems. In case operating system has other default folder/directory for fonts, you should use following line of code before performing any operation using Aspose.PDF.

Aspose.Pdf.Text.FontRepository.Sources.Add( new FolderFontSource( "<user's path to ms fonts>" ));

In case you still face any issue, please share your sample PDF document with us. We will test the scenario in our environment and address it accordingly.

3

This seems to work for some documents.

This is the docker container I used:

FROM mcr.microsoft.com/dotnet/core/sdk:3.1

WORKDIR /app

RUN apt-get update

# install ttf-mscorefonts-installer
RUN echo "deb http://httpredir.debian.org/debian jessie main contrib" > /etc/apt/sources.list \
    && echo "deb http://security.debian.org/ jessie/updates main contrib" >> /etc/apt/sources.list \
    && echo "ttf-mscorefonts-installer msttcorefonts/accepted-mscorefonts-eula select true" | debconf-set-selections \
    && apt-get update \
    && apt-get install -y ttf-mscorefonts-installer \
    && apt-get clean \
    && apt-get autoremove -y \
    && rm -rf /var/lib/apt/lists/*

RUN apt-get update && apt-get install -y libfontconfig1 libgdiplus

COPY . ./
RUN dotnet publish -c Release -o out

ENV ASPNETCORE_URLS "http://0.0.0.0:8000"

ENTRYPOINT [ "dotnet", "out/MyProject.dll"]
4

@samuelkdavis

Please share the document for which you are facing the error after even following the above shared suggestions. We will further proceed to assist you accordingly.