Go to your ADO link from where you want the backup of all the tasks
In my case Link
In my case I am taking the "DynamicsProject" as shown in the picture below
open the project, go to board -> queries as shown in the picture below
click on "New query", you will see a window like below
In that, click on Run query, as shown below
Now click on "Save query", a new popup will be shown, now enter the name of the query, in my case I am taking "TestQuery"
Click on the "Column option" as shown in the picture below
a new window will pop up like below
Now click on add a column and select the column,
and in the same way keep on adding the column and add all the columns in it
Now click on "Export to CSV", now save the CSV file in the desktop
Please Note: You need to do some changes in the CSV file as written below
{
* Remove the ID column from the CSV file as this will be set by next ADO project itself
* Following fields are read only and can't be uploaded via CSV, so remove them: ID, attached file count, authorized date, board column done, comment count, node name, related link count, remote link count, rev, revised date, state change date, team project, watermark, parent, board column, closed date, activated date, state, reason, changed date, created date, activated by, resolved date, resolved reason, resolved by, closed by.
* Also change the email address for fileds like assigned to, in the CSV as the email address in one organization must be different for the different user in the other organization. for example: in 1st organization email address is Prasad@Illuminatechnology.com and in second it will be PrasadV@Pepsi.com. Use find and replace in Excel to change all at once.
}
Now go to the second project in any organization, where you want to import the work items, bugs and all (In my case I am going to "Dynamics project Two" in the same organization)
Now go to the project and the go to board > work item
now click on "Import Work Items"
Now it will open new window like below
from this choose the CSV file and click on Import as shown below
Tada!!!