Question edited, I've mixed up with the errors
Tried both on WXM Admin 10.6.1 and PRO 2.2.4 (using postgres 9.5) and I get this message.
"The requested database does not contain the required Workflow Manager schema"
In PRO I am asked: Do you want to create the schema. I click yes.
and when I create a workflow database I get this error:
Not sure what I should look for.
I also tried to set up everything as this article says: Startup Guide: Setting up a Postgres Enterprise Database for ArcGIS Workflow Manager
by following this guide I realized that C:\PostgreSQL\pg95\lib\postgresql
does not exist even though Postgres was already installed.
(I copied the database support file into C:\Program Files\PostgreSQL\9.5\lib )
I works fine until the Create Workflow Database.
Not sure why, but:
Yesterday I created a ent. geodatabase for WXM
Then I tried to create a WXM database and I couldn't as per question posted.
Today I tried again and nothing. Then I tried to create a new table in an already connected geodb and I got the message: something like "cannot create a table as the spatial component is missing" (sorry I have already forgotten the error message).
I went to check if the st_geometry.dll was there and it was but I decided to overwrite the same and now I could create a Workflow geodatabase.
Problem solved for now.