[mail@remote.domain] INVALID_ADDRESS, ERROR_CODE :550, ERROR_CODE :5.1.0 <mail@zoho-hosted.domain>: Sender address rejected: User unknown in virtual alias table

[mail@remote.domain] INVALID_ADDRESS, ERROR_CODE :550, ERROR_CODE :5.1.0 <mail@zoho-hosted.domain>: Sender address rejected: User unknown in virtual alias table

[ mail@remote.domain] INVALID_ADDRESS, ERROR_CODE :550, ERROR_CODE :5.1.0 < mail@zoho-hosted.domain>: Sender address rejected: User unknown in virtual alias table

I get this error msg when I try to send an email from zoho to a specific remote domain. From gmail/hotmail etc I'm able to send to this domain. Also from the zoho account i'm able to send email to other domains.

What could be the problem? Thank you.