Hi @hwwangf ,
I was playing around with the “Call local Workflow” node, too. I was trying to execute it in batch mode but couldn’t get it to run. Then I came across this post from February this year that may (? 
) be relevant to you:
https://forum.knime.com/t/execute-workflow-with-command-line-execute-failed-cannot-determine-id-of-local-mountpoint/61560/2
Like I said I ran into some problems with calling the nested workflows in batch mode:
“C:\Program Files\KNIME\knime.exe” -nosave -consoleLog -noexit -nosplash -reset -application org.knime.product.KNIME_BATCH_APPLICATION -workflowDir=“C:\Users\XXX\knime-workspace\2020_08_10_Multiple_Reports_Parent_Workflow”
It returned the following message in the knime.log:
java.io.IOException: Cannot determine ID of local mountpoint
[…]
Caused by: java.lang.IllegalStateException: Cannot determine ID of local mountpoint
When I used the mountpoint connector as shown in the linked thread, I could successfully execute the nodes. I’m not sure whether our problems are the same but maybe you can have a look.
I’m currently on KNIME version 4.7.5 with updated nodes, and I think that the type of image that you import might be relevant, too (embedded vs URI vs …).
Parent workflow settings:
Child work flow report template with embedded image:
