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We are unable to reproduce the mentioned “Page Layout” issue with given details. We have tried to reproduce the issue at our end using below sample code.
// Loads template Word document.
WordDocument wordDocument = new WordDocument("Source.doc");
// Adds paragraph with text to the section.
wordDocument.LastSection.AddParagraph().AppendText("End of section added one paragraph");
// Modifies the text of first paragraph of the section.
wordDocument.LastSection.Paragraphs.Text = "First paragrph of section modified";
// Modifies paragrah format with back color for particular paragraph.
wordDocument.LastSection.Paragraphs.ParagraphFormat.BackColor = Color.Yellow;
// Saves and close the Word document instance.
We could see the following comparison result while opening the given Word documents in Microsoft Word application. Can you please confirm us whether you are representing this differences as an issue with "Page Layout", if so then kindly share your code snippets or sample on how you have generated this “New.doc” Word document from “Source.doc” Word document there by we could analyze further on the reported issue.
Source and New Word document at your side
Source and resultant Word document at our side
If not the above differences are the reported issues, then kindly update us clear description of the issue along with screen shot to illustrate the same which will helpful to provide you the appropriate solution at the earliest..
Please refer the UG link to know more about how to specify page properties using DocIO.
Please let us know if you have any other questions.