Cannot load retrieval-0.5-SNAPSHOT.war.original on tomcat #3

Hi, I'm pretty new to all of this and had a problem. First of all, installed tomcat according to: https://www.digitalocean.com/community/tutorials/how-to-install-and-configure-redis-on-ubuntu-16-04
and it works since I deployed successfully a sample.war file.

Then installed redis and deployed retrieval-0.5-SNAPSHOT.war.original to webapps in tomcat (renamed the file to retrieval.war).

And when trying to load retrieval.war this error arises:
FAILURE - Couldn't load application on context path [/retrieval]
FAILURE - Found exception [org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[/retrieval]]