Often emails come from unknown senders with a hidden address. Before opening such a letter, you need to find out who is the owner of this mailbox.
Find out who the account is registered to using search engines. Enter the following query into the search bar: "Mailbox @ domain". In the event that the address you specified at least once "lit up" on the Internet - the system will show you the information who is the owner of the e-mail box, identical to your request.
If you still opened a letter from an unknown sender, write to it and ask for an answer. After you receive an answer, you will be able to find out the ip-address of the computer from which the letter was sent and which city this ip-address belongs to. The list of owners of this e-mail box will be significantly reduced.
Go to the forum and post a topic with a question about such letters. Maybe someone has already encountered such mailings and knows who the mail system account is registered to.
Visit various social networks where you can find out the necessary information about the owner of a particular email address. If the letter came from the mail.ru service, try searching for the mailbox owner on the My World social network. To do this, simply enter the required address in the search bar and click on "Find". If the email is valid and the owner is registered with My World, you will receive information about the owner of the address. You can also find the mail owner on the Ya.ru social network, if the letter came from the Yandex.ru service. in the same way, look for the owner of the account on VKontakte, Odnoklassniki, etc.
Go to the website www.nigma.ru. Search for the address you are interested in in this system. She finds information in several search engines at once, then gives it out in one general list.
Use the online special services that provide information about the owners of e-mail boxes at your request. Enter the appropriate query in the search engine.