刚才信被退回。翻译成英文

The letter was returned/或:sent back just now.

这是Mail delivery failed，系统退信经常用的，通常可以意译为：
A message that you sent could not be delivered to one or more of its
recipients. 我经常收到的系统自动回复。
直译的话可以是 The mail you sent was returned just now.

刚才信被退回。
The letter was returned just now.

The delivery was rejected just now

The letter had returned just now .