Hi,
After the error. if its not going any where then just log off from server.
later you can go to ecc system, at SE11 open your extract structure. from end row,you can delete appended structure.
Actually your data source was was running on delta, in that case how you think about deletion.
Delete option never use for used data sources.
Now to Go RSA5 and try to activate it again.
Go to SMQ1,SM13 and LBWQ - check is there any Queues which are related to 02 application. if you seen them delete it.
Thanks