java.lang.NoClassDefFoundError: org/apache/http/conn/scheme/SchemeSocketFactory

Question

I am tring to send mail by AWSCredentials but getting an exception

java.lang.NoClassDefFoundError: org/apache/http/conn/scheme/SchemeSocketFactory

Answer 1

In my case, I had two libraries that I created in Netbeans 7.2: one for the Apache Commons Codec 1.6, and one for the Apache Commons HttpClient 4.2.2. In this case, because the library I made for HttpClient also contained the Codec 1.6 jar, I was getting this same error.

Be sure you don't have two of the same libraries referenced in your class path, or two conflicting versions of the same library.