If you have Outlook installed as default mail client running the latest eM Client V11.0.473 via the release history page, then your issue sounds similar to this issue in the following thread where there is an update fix you could try.”at the end of that thread” Beta feedback - Error box - #11 by Jitka
If you don’t have eM Client set as default mail client and are happy to have it set as default, then see @gary posts below in the following threads for Windows 11 and Windows 10 how to set defaults. Then reboot your computer once set and see if that fixes that error you are getting.
Set Windows 11 as default mail client
Set Windows 10 as default mail client
If none of the above thread posts help you then suggest you email [email protected]