Issue with .docx,.pptx,.xlsx and .msg email attachments

Hi - Sending email through smtp with attachments of these types in SAg 10.3, I am facing issue while opening email attachments like .dox,.pptx, .xlsx and .mssg files. When I try to open the email attachment then got the error that “found a problem to open the file.”

Tried with below content types

Attached error screen !!!

Appreciate your thoughts and suggestions to fix this issue!.