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Check if there is no nexus running. If not, delete
checkState()is Static convenience methods that help a method or constructor check whether it was invoked correctly (whether its preconditions have been met). This occurs when the precondition does not met.
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java.lang.IllegalStateException: The driver executable does not exist: C:\Users\Aurora\Downloads\geckodriver-v0.10.0-win64.zip\geckodriver.exe