On this site you can find information about error codes in DMS Export
In EmmaSped when you receive an error DMS system to system integration, then you can see the error in Toldtabel (F6).
In EmmaSped the DMS export will be in a status 4 in EmmaSped.
if you click on the DMS Export that are in status 4, then you will be able to see the error code here
This error message is send back directly from the DMS solution.
You can see an excel sheet from Toldstyrelsen here on this LINK
If you have a question about an error, we recommend that you contact ToldStyrelsen Help Desk