Hi Savio,
the Process Portal application makes use of a number of "process app" artifacts that must be available in the product database. In case you installed with "deferSchemaCreation=true", you need to manually run the bootstrap command to fill the database with system apps.
See https://www.ibm.com/support/knowledgecenter/SS8JB4_19.x/com.ibm.wbpm.imuc.doc/topics/db_bootstrap_nd_win.html?view=kc
Note that having starting your environment without bootstrapping can lead to unexpected side effects (such as the primary administrative user being added to the database with an unusual numeric representation). I'd recommend to recreate the database from scratch.
I'd also recommend review the logs top to bottom. In case bootstrap completed, your server may fail to connect to the database all together...
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Jens Engelke
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