If you carn’t delete the trash in eM Client “and there is no emails in the trash folder online”, then that usually means you have a database problem and need to manually run the repair.
So if you have Windows see @Gary post below in the following thread how to manually run that.
https://forum.emclient.com/t/item-cannot-be-delete-from-trash/95660/2
If you have Mac “close eM Client” and then “open the Terminal app via either Launchpad or Utilities” on the Mac. Then Paste and run the following command.
/Applications/eM\ Client.app/Contents/MacOS/eM\ Client /dbrepair
I now sent myself a test email from eM Client. It is visible on the providers side on the IMAP server in my inbox and in sent mails but it is not shown in eM Client inbox nor sent mails
Edit: I have the same discrepancy with Apple Mail on my iPhone now. I guess the index on my providers (IMAP) side is broken somwhow
Yes there might be some eg: Mail server problem atm as it’s now happening in both mail clients.