Going through another strange issue:

Excel workbook loads fine with the main site url, but for alternate access mapped url (for public facing), it is stuck on loading state.

Checked already with different configurations in excel trusted file locations.

Hi Rizzk,

Was there any error when loading the excel files?

I recommend to use F12 tool or fiddler to check if there are any errors on the requests when opening excel files using Excel Service.

Please also add the public site to the trusted sites in Internet Explorer and then compare the results.

Best regards.

Thanks