Accidently sending from 2 accounts

I have two accounts. Why does e-mail written to send from one get sent also from the other? Recipients are actually receiving two copies of the same mail from both of my addresses.

Hello,

do you have setup any rule that does this? (Tools - Rules)

regards
Jan

Nope. Only rules are Spam filter and Blacklist.

Hello,

sorry for delayed answer.

Is this happening really for all your emails? If true then I would like to see it on my own eyes over remote control if it is okay for you.

you can contact me on [email protected] where we will arrange details.

regards
Jan