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Please note that Aspose.Words requires TrueType fonts when rendering document to fixed-page formats (JPEG, PNG, PDF or XPS). You need to install fonts that are used in your document on the machine where you are converting documents to PDF. Please refer to the following articles:
Using TrueType Fonts
Manipulating and Substitution TrueType Fonts
You are using old version of Aspose.Words. We suggest you please try the latest version of Aspose.Words for Java 21.2.
If you still face problem, please ZIP and attach your input Word document here for testing. We will investigate the issue and provide you more information on it.