DRS Softech is providing a excellent solution named as IMAP Backup Tool. This is a professional tool that converts your IMAP mails into any other email client or in multiple file format. With the help of this tool users can set up a automatic backup process for their emails. It is a very easy to use tool and also offers free demo version to its users. You can download the tool and check its functionality.

Check that IMAP is turned on
On your computer, open Gmail.
In the top right, click Settings. See all settings.
Click on the Forwarding and POP/IMAP tab.
In the 'IMAP access' section, select Enable IMAP.
Click Save changes.
Jimmy Wick
I understand your worries are justified, especially if you work with emails all the time. I haven't had this problem yet, but my friend has. Then he used the services of this post office at https://www.outlooktransfer.com/products/incredimail-to-outlook-transfer/. He said that as soon as his old post office stopped working he lost any hope of recovering materials from there. But the capabilities of the new outlook software almost saved his life.
Useful information, but I have a little bit of a different problem. I want to change my macbook to an asus computer, but am very worried about transferring important information for me. Perhaps someone has used resources on this topic and can share.