How to transfer a site and not lose mail?

Question

Email

The company has a website located on an unknown hosting, it seems to be the developer's private hosting, no one has access to it, the developer no longer exists. If the site suddenly falls, then no one will be able to restore it. There is also corporate mail at biz.mail.ru attached to a domain like [email protected]

From what I could get as a result of excavations, access to ftp and to the WordPress admin panel, access to the biz.mail.ru account and the domain tenant, support from which is only "you give us NS hosting, we will set it up for ourselves, We don't have a private office.

The task is to transfer the site to a new hosting without losing the functionality of mail.

Question 1: Is it possible to switch to a new hosting without having access to the old one, will there be any conflicts?
Question 2: Will there be a conflict between the mx records of the new and old hosting, will I be able to keep my mail working?

If it is not immediately clear what I need, ask questions, because. I myself have not really formulated in my head what's what.

Answer 1

Question 1: Is it possible to switch to a new hosting without having access to the old one, will there be any conflicts?
Can.
The easiest way:
Download the site via FTP.
Upload via FTP phpmyadmin and merge the database. Access to the database is in the WP config.
We deploy site backup on a new hosting. We check.
The site has moved to a different host.
Let's go further.
1) We rewrite DNS records from the current NS (Set the minimum Timeout for A records)
2) We ask you to register your NS - and transfer them to Yandex, Selectel, to a new hoster or to any other dns hosting - free or paid. Yandex and Selectel are free.
3) We change the A record to the IP that the new host gave you.
At this point, the site on the new hosting responds, the mail goes through the MX record that you copied and, in general, everything should be ok.
4) We transfer the domain from sin away to a normal registrar.
If there is access to biz.mail.ru and there is no desire to leave them, we leave it as it is.
If there is a desire to leave, we set up imap on the mailboxes and stupidly transfer mail from old to new as a client. There was a good instruction in the manuals for Yandex mail for domains.

Answer 2

There shouldn't be any problems.
The domain is yours - as you want, and set it up.
You can even connect to Yandex, even to Google if you wish.
The circulation of mail, in theory, is not connected with hosting at all. Website - separately, mail - separately. Only the domain name is common.
Moving a site can be tricky. But nothing that could not be solved by setting up hosting or contacting those. hosting support. You have access to FTP and the database, which means you can export everything and upload it to a new hosting, and then deal with small settings so that everything works as before.

Answer 3

as they said, you can transfer mail without problems by setting up your domain (DNS), but it is worth remembering that the zone update can take up to 3 days, so it is recommended to change the settings and start transferring on Friday evening, so that by Monday you will be on a new mail server. I think that on the weekend there will be a minimum movement of your mail. mx records should be changed to new ones immediately.
Of course, you can always get mail from old servers (if the name of the mail server is not related to the name of your domain), but as a rule, this causes difficulties for ordinary employees.

Answer 4

Everything will go without problems, you will lose old letters on the server