After upgrading Appian, you see errors in the application server log that state that a class could not be instantiated. The server will start up, however odd behaviour is noticed once navigating through the environment. The log messages are similar to the ones below:
ERROR [stderr] (MSC service thread 1-7) log4j:ERROR Could not instantiate class [com.appiancorp.security.external.ScsActivityLoggerImpl$ScsActivityLoggerCsvLayout].ERROR [stderr] (MSC service thread 1-7) java.lang.ClassNotFoundException: com.appiancorp.security.external.ScsActivityLoggerImpl$ScsActivityLoggerCsvLayout from [Module "deployment.suite.ear:main" from Service Module Loader]
The above example is caused when an appian_log4j.properties file is copied over from a previous installation instead of using the file from the fresh installation.
In general, you should not merge base product files from previous versions of Appian with new versions of Appian.
For the above example, replace the appian_log4j.properties file with an out of the box version of the file. Following this you will be able to start up the application server.
In general, use all base product files from your fresh installation to prevent this sort of error from occurring.
This article applies to all versions of Appian.
Last Reviewed: August 2017