e-mails can not be deleted

[secret4lovers]

I have 3 mail accounts and in 2 of them i can not delete old e-mails. After I delete, the messeges look like is erased , but when press "check mail" I see this messages again. I saw inside mail box and the messeges is still on server. My question is why it`s imposible to erase messages only in 2 accounts? Why the 3rd mail work ok (all 3 accounts is on the same server)
Thank you.

[kuske]

What is the name of your trash folder?
Something with special chars like "gelöschte Objekte" ?