deleted attachment is not removed

I have serveral mails with an attachment, that keeps popping back after I removed it. It can be a drawing (.dwg) but also pdf files. From most emails i am able to remove these attachments, but not from all of my mails.

I am using eM Client 7.0

Any Idea?

Hello Hans,

Could we please ask who is your provider and how is your account set up? Does this happen on the same account? Could you also tell us what version you use?

Thank you,