@mrintech
The plugin which you are using creates and writes to a sitemap.xml file. Just copy this file into your root directory. This is what iMav means. On the other hand, I am not sure if it will work. Could be just a overlapping of events that occurred with iMav.
Also, if you are moving database-driven website, you will have to export and import databases appropriately and also change the database connection details such as username, password, database name in the settings or config files!
Also, it it matters to you, you should backup the logs such as error logs, access logs, visitors stats. etc.
Backup your mails as well.
Best way to achieve all this id download a full backup of your site from your control panel.
Tip: Whenever moving your sites, create a index page that shall send "HTTP 503-service temporarily unavailable code; Try after some time" code to the spider and browsers!