Track email to closed opp

Hello everyone,

We've just migrated from SugarCRM to Dynamics 365 & so far everything is going well.  I've solved most problems with the help of Google, but this one has me stumped.

We use Outlook 2016 & can track emails to records in Dynamics.  That is, unless it's a won opportunity.  I thought the record might somehow lock once the opp was won, but I'm still able to add notes & call information.  Outlook can see other records, but doesn't list any won opportunities.  It seems like I'm the only person in the world who's had this problem, or is it not a problem & just how Dynamics works?

Thanks.

John