To export users from MindBody Online:
Select Reports > Clients (on the left) > Membership
On the Membership report, select Generate
On the right hand side column (Members), click on the Total - ### link
On the following page, select the yellow tag icon at the top of the page (next to the Generate button)
Once the page refreshes, select "OK" for the "Resulting clients are tagged" pop up.
Select Reports > Clients > Mailing Lists
Change the third filter (Client's Opt-in status) to "All clients"
Check the box for Tagged clients only (###) > Generate
Next to the Generate button, select the XLS icon to export that list to Excel.