Hi
i have managed to open .xls files form mail app by adding document type to the project build and set the Types field to “com.microsoft.excel.xls” (see screen shot).
I want to do the same with xlsx files but can’t do it. I tried to add “com.microsoft.excel.xlsx” but it didn’t work

I solved that by defining custom UTI as follows. Try to add these definitions into your info.plist. It works as expected.
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