Can you please validate below settings?
When will a template show as an Open in Excel option?
When a template listed in the Common > Common > Office integration > Document templates form (DocuTemplate) has ShowInOpenInOfficeMenu set to Yes and has the same root datasource (table) as the current form, it will be added as an option in the Open in Excel section of the Open in Microsoft Office menu. The following image shows the Document templates form.
When adding a template into the Document Templates form, it is added for that instance and is referred to as a “user-defined” template. Templates can also be defined in metadata and code and loaded automatically, thus making them “system-defined” templates. To create a system-defined template using metadata and code, you need to do the following:
- Define the template.
- Create a new resource in a project.
- Define a new class that extends the DocuTemplateRegistrationBase class and add an implementation of the registerTemplates method.
The LedgerJournalLineEntryTemplateRegistration and FMTemplateRegistrations classes are good examples of template registrations defined in code. The LedgerJournalLineEntryTemplate and FMTemplateCustomersWithLocations resources are the corresponding templates stored in metadata as resources. When a template has a registration class, it will be loaded when the Reload system templates button is clicked in the Document Templates form.
docs.microsoft.com/.../office-integration-edit-excel
