If one sends a Webservice(SOAP) request with the default JMeter installation, an error is thrown: java.lang.NoClassDefFoundError: javax/mail/MessagingException. This error is visible both in Jmeter.log (located in the JMeter bin directory) and a result sampler like the View Results Tree.
The solution for this problem is to download and install the mail.jar and activiation.jar libraries. Download java mail from Sun and java activation from Sun. Extract respectively mail.jar and activiation.rar from the downloaded zip archives, and put them in your Jmeter lib folder. For instance: D:\machtst\My Documents\Tools\jakarta-jmeter-2.3.2\lib\
It's important to close JMeter and reopen it again, so JMeter can load the libraries. If you run your test again, the error should be gone.
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