Detailed Description and Symptoms
When attempting to start the SAP agent, the message below occurs and the agent ends abnormally:
U2004161 No connection assigned to the ABAP stack..
Go into Client 0 to the HOSTS folder. Double click on the agent to edit it. Go to the Agents tab and be sure that a connection object exists. Confirm that the information in the connection object is correct. Solution
1) Log into Client 0.
2) Create a Connection object and fill in the pertinent information.
3) Go to the HOSTS folder and double-click on or edit the agent.
4) Go to the Agents tab and assign the Connection object from step 2 to the agent.
Attempt to restart the agent and the error should be resolved.
If you get the error with an existing Connection object please delete it, create a new Connection object with the same name and the problem should be solved as well.