JavaWeb web small white one, before after the project constructed can run directly, but now can't run, and successful operation of the project before didn't also way,
Built a again today, or an error

New run directly after an error:
D: \ Tomcat8 \ bin \ catalina bat run
[12:29:16 2020-06-07, 087] an Artifact FuWeb: war exploded: Waiting for the server connection to start an Artifact deployment...
Using CATALINA_BASE: "C: \ Users \ \. Dell IntelliJIdea2018.3 \ system \ tomcat \ Tomcat_8_0_36_FuWeb"
Using the CATALINA_HOME: "D: \ Tomcat8
"Using CATALINA_TMPDIR: "D: \ Tomcat8 \ "
Using JRE_HOME: "D: \ JDK \ jdk8_231"
Using the CLASSPATH: "D: \ Tomcat8 \ bin \ the bootstrap jar; D: \ Tomcat8 \ bin \ tomcat - juli. Jar
"07 - Jun - 2020 12:29:17. 028 SEVERE [main] org.. Apache tomcat. Util. Digester. The digester. StartElement the Begin event threw the error
Java. Lang. NoClassDefFoundError: javax.mail HTTP/it/servlet/
The at Java. Lang. This defineClass1 (Native Method)
The at Java. Lang. This. DefineClass (756). This Java:
The at Java. Security. SecureClassLoader. DefineClass (SecureClassLoader. Java: 142)
The at java.net.URLClassLoader.defineClass URLClassLoader. Java: (468)
The at java.net.URLClassLoader.access$100 URLClassLoader. Java: (74)
The at java.net.URLClassLoader$1.run URLClassLoader. Java: (369)
. At the back of the omitted

Create a new servlet after
Direct error
Always resolve a symbol 'HttpServlet'

Look at Libraries is completely empty
But before that, no problem, today not, suddenly,