1. Check if your file needs to enter a password when you open your file. If so, just enter the password and the file will be opened, otherwise, we can't open this kind of file.
2. Check if your file is damaged. If so, please load the normal file.
3. If not the above, please contact us and provide us with your file. If your file is very big, you can upload it to Google Drive and send the link to us.