Outlook 365 PC is opening the wrong email.

Hello,

When I click once on a new email just to preview it, rather than previewing the chosen email, Outlook opens in a seperate window the email I received just before the new email in the list. 

Previously, Outlook PC had crashed on my PC losing the correct server information for my OVH Pro email account. I had to reset the IMAP settings and now everything seems to be fine, except for this weird "problem".

Any ideas ? 

Thanks for your feedback