I am having a similar problem. I received the same error. To ensure my copy of Autopsy was not corrupt, I uninstalled it, downloaded a new copy and installed the new copy. After receiving the same message, I updated Java and Windows 10. Still received the same error:
Failed to create database
Solr Keyword Search Service Error
Could not close case resources for Solr keyword Search Service service: java.lang.NullPointerException
As the error appeared to be related to the Keyword Search Service, I disabled the keywordsearch under tools->Plugins->Installed.
When I attempted to create a new case I did not get the error related to Solr Keyword Search Service. Instead I just received an error stating “Cannot create case. Failed to create case database: .” However, when I go to the location the case should have been saved to, autopsy.db is present and looking at the db with DB Browser appears to have some data. Any help would be appreciated.