I cannot read your mails

I used to be able to read emails you sent me, especially with the claims on my account. Now I cannot read. I'm not sure what program you are using to send your mails - but the email appears as blank with an attachment. When I try to open on my mobile phone, the attachment doesn't work. On my computer, there's no program that opens the attachment. So basically, you are communicating with me, but I have no idea of what you're trying to say as I cannot access whatever information you are trying to convey