Michael Bowen

Hi @AdMSilvan, unfortunately the OOXML SDK does not distinguish between strict and transitional. And adding this functionality would mean rewriting significant portions of the codebase, so it is not something...

- #1031 Resolves this issue.

Hi @Asbjoedt , thanks for the detailed description. I'll look into this issue too and let you know if I can find the issue.

@Asbjoedt , how is the customUI part being added to the file?

Hi @Asbjoedt , To give you a better explanation, I'm asking how the file was created is because, if you look at the underlying xml parts of data sample you...

@Asbjoedt I contribute to a VS Code extension that makes it easier to edit OOXML files and rezip the contents. It might if you need to look at the underlying...

I don't know a fix, but the reason you get this error is because `ribbon.RootElement.NamespaceUri` is the root namespace and is not in `ribbon.RootElement.NamespaceDeclarations`. If you step through the code,...

@Asbjoedt , I haven't found why `spreadsheet?.WorkbookPart?.Workbook.AbsolutePath` is null when the part is in the workbook, I'll keep looking into that, but in the meantime I have a workaround to...

Hi @Asbjoedt, It turns out this is by design. The `SpreadsheetDocument.Open` method takes an optional third argument `openSettings`, which is the advanced settings for opening the document. [See more at...

Hi @Asbjoedt, try this: ```csharp using (SpreadsheetDocument spreadsheet = SpreadsheetDocument.Open(file, true, new OpenSettings() { MarkupCompatibilityProcessSettings = new MarkupCompatibilityProcessSettings(MarkupCompatibilityProcessMode.ProcessAllParts, FileFormatVersions.Office2013) })) { spreadsheet?.WorkbookPart?.Workbook?.AbsolutePath?.Remove(); spreadsheet?.Dispose(); } ```