Extension compatibility is generating error when uploading files

Hello,
Please help me by solving the following question.

I was uploading files with the extension .doc, .xls and ppt but I changed the name of the files to special characters and I got a message saying that I should change them to the extension .docx, .xlsx and .pptx, do it and I duplicate the files but it does not open them, they generate an error.

Hello,
Please describe step-by-step what you are trying to do. doc/xls/ppt files are converted automatically when they are uploaded to the Workspace portal. Are you using some other DMS? Please provide details.