Sudden java.lang.ClassNotFoundException: org.apache.log4j.Category When Launching WebLogic Console in JDeveloper

When launching the WebLogic console in JDeveloper last week, the below error was returned. I've worked with my DBA team and other support staff, and none of them know why this is being reported; the version of JDeveloper I'm using is 12.2.1.4 and is the official version we use in our organization.

When we open the log4.jar, it does contain the Category class, but maybe there are other log4.jar jars somewhere else that WebLogic is trying to use. If anyone has any insight on this, I'd greatly appreciate it. I've hit a complete dead end in trying to solve this. Thanks. --JR

Error deploying Internal Application: weblogic.application.ModuleException: java.lang.ClassNotFoundException: org.apache.log4j.Category
weblogic.application.utils.StateChangeException: weblogic.application.ModuleException: java.lang.ClassNotFoundException: org.apache.log4j.Category
    at weblogic.application.utils.StateMachineDriver.nextState(StateMachineDriver.java:58)
    at weblogic.application.services.BackgroundDeploymentManagerService$BackgroundDeployAction.run(BackgroundDeploymentManagerService.java:396)
    at weblogic.application.services.BackgroundDeploymentManagerService$OnDemandBackgroundDeployAction.run(BackgroundDeploymentManagerService.java:458)
    at weblogic.work.SelfTuningWorkManagerImpl$WorkAdapterImpl.run(SelfTuningWorkManagerImpl.java:681)
    at weblogic.invocation.ComponentInvocationContextManager._runAs(ComponentInvocationContextManager.java:352)
    Truncated. see log file for complete stacktrace
Caused By: weblogic.application.ModuleException: java.lang.ClassNotFoundException: org.apache.log4j.Category
    at weblogic.application.internal.ExtensibleModuleWrapper.start(ExtensibleModuleWrapper.java:140)
    at weblogic.application.internal.flow.ModuleListenerInvoker.start(ModuleListenerInvoker.java:124)
    at weblogic.application.internal.flow.ModuleStateDriver$3.next(ModuleStateDriver.java:233)
    at weblogic.application.internal.flow.ModuleStateDriver$3.next(ModuleStateDriver.java:228)
    at weblogic.application.utils.StateMachineDriver.nextState(StateMachineDriver.java:45)
    Truncated. see log file for complete stacktrace
Caused By: java.lang.ClassNotFoundException: org.apache.log4j.Category
    at weblogic.utils.classloaders.GenericClassLoader.findLocalClass(GenericClassLoader.java:1029)
    at weblogic.utils.classloaders.GenericClassLoader.findClass(GenericClassLoader.java:990)
    at weblogic.utils.classloaders.GenericClassLoader.doFindClass(GenericClassLoader.java:611)
    at weblogic.utils.classloaders.GenericClassLoader.loadClass(GenericClassLoader.java:543)
    at weblogic.utils.classloaders.GenericClassLoader.loadClass(GenericClassLoader.java:496)
    Truncated. see log file for complete stacktrace