If you are on this page you probably are looking for a solution to get rid of the annoying message in SAP saying "No vendor specified".I will start with the solution and go onto the details on why this is happening
1. Goto SE91, enter 00 in Message Class and 001 in Message number and click on Display. You should see the screen below
Now you know why this is happening and the following steps show how to correct this
2.Click on change Button, and on the pop up choose "Maintain in Original language", you should see the German versions of the messages.
3. Click on menu Goto->Translation, in the target language enter 'EN'. Replace text " No vendor specified" with "&1&2&3&4&5&6&7&8" and click on Save.
4. Now rerun the transaction where you got the "No Vendor specified" and you should see the right text.
Details..... to be continued