The file content is empty

id:content-empty

The error indicates, that the file contains an empty qmail configuration. This will store incoming mails directly to the maildir ~/Maildir and so bypasses the mail setup. In the standard mail system we can only support full mailaddresses as forwards.

You need to check in what way you want to use this mailaddress and the forward target, you should set up either a real forward to a mailaddress or a mailbox for this mail.

Error

Error: This configuration is probably not working as expected in the standard mail system. This is why you should recreate this mailaddress yourself using the uberspace mail commands.