I want to add an XML expansion pack to my Excel file. However, when I was attempting to attach the manifest.xml file through "XML Expansion Packs" option on Developer tab in excel, it is showing me the error "The file could not be installed because there was a problem with the security certificate. The XML expansion pack may not work as expected. For more information, contact your administrator". Can anyone help me out?
Below are the links of my excel sheet and manifest.xml respectively.
Trial.xlsx: https://drive.google.com/file/d/14Ep6HBmGC2SP3ohGnxwGdrzfa_fyiF7K/view?usp=sharing
manifest.xml: https://drive.google.com/file/d/1GZoQJDIiFjd-udHYO1Yg4LE0N9f5WdC7/view?usp=sharing