OUTLOOK JUNK FOLDER DUPLICATION BUG

Having just installed Win10 on this laptop, O365 was next on the list. Having gone through the task of installing and verifying, I launched Outlook and noticed that JUNK had duplicated itself.

When I click on either, it works OK. But if I then click on the other, the two folders seem to animate, running around each other in 'vertical circles' until Outlook crashes. I then have the option to recover, only to find the two appear once again. Earlier on Tuesday (3 July) I had no end of trouble installing Outlook on another computer system, and I wonder if this has had an impact?