Delete BPEL Composites which are in unknown state : Failed to make composite state update: Composite "" does not exist.

When your BPEL Processes goes into the unknown state and in that case you can't do anything(shutdown, startup, retired etc.) and when you click on any action following error is thrown:

Internal error: Failed to make composite state update: Composite "Default/HelloWorld!1.0*soa_cad506cc-72bd-4b2c-9990-5c84ea3861c7" does not exist.

In that case you can delete composite entry from the MDS and after restarting the server unknown composites are not visible in em console.

How to remove composite entry from MDS

1. Run wlst.sh ( /app1/Oracle/Middleware/Oracle_SOA1/common/bin/wlst.sh)
2. Connect to SOA Server Instance i.e. connect('weblogic', 'weblogic123', 't3://10.3.15.102:8001')
3. Export the metadata. By running the command  exportMetadata(application='soa-infra', server='soa_server1', toLocation='/home/oracle/mds', docs='/**'), here "/home/oracle/mds"  is the location on the machine where all the MDS data exported.
4. After Exporting the MDS, two folder are created in "/home/oracle/mds" i.e. deployed-composites and soa.
5. Now  go to deployed-composites folder there is deployed-composite.xml, open that file in an editor and remove all the faulted composite entry.
6. After saving the file, Import the MDS by running the command importMetadata(application='soa-infra',server='soa_server1', fromLocation='/home/oracle/mds',docs='/**')
7. Restart the SOA Server.