IDoc error on outbound side

Hi.

I'm setting up a communication with (JMS adapter -> XI -> IDoc adapter).

No w to the problem. When we send the message with the IDoc adapter we get the following error.

Message has error status on outbd. side

We can see this message when I put my cursor over the red flag in the outbound status column in SXMB_MONI.

I do not think there's anything wrong with the adapter because we are using it to send an other IDoc and that IDoc gets processed correctly to the target system.

What can cause the error on the that I get above?

BR

Kalle