Please see the steps on our website about the COM error:
https://support.clarivate.com/Endnote/s/article/EndNote-Mac-COM-exception-error?language=en_US
If this does not resolve the issue:
Please contact Technical Support directly
1-800-336-4474 option 4 then 1 or
https://support.clarivate.com/Endnote/s/technicalsupport?language=en_US