Игнорировать предупреждение OpenXML

 
                IgnoredErrors ignoredErrors = new IgnoredErrors();
                IgnoredError ignoredError = new IgnoredError()
                {
                    SequenceOfReferences = new ListValue<StringValue> { InnerText = "A:Z" },
                    NumberStoredAsText = true
                };
                ignoredErrors.Append(ignoredError);
                worksheetPart.Worksheet.Append(ignoredErrors);
                sheets.Append(sheet);
Sore Stork