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If you installed the Apache Agent and are experiencing problems, try these suggestions for investigating installation issues.
Undefined Symbol Error
An error message similar to the following typically indicates that you have loaded the incorrect agent library for the version of Apache you are using.
Check the description of LoadModule on Install the Apache Agent to make sure that you are loading the correct module. For example, For Apache 2.2, your LoadModule directive should be:
App Crash Caused by libstdc++ Mismatch
The AppDynamics agent uses libstc++ v6. If your application uses a different version of libstc++ and the modules were not loaded in the correct order, the wrong library routines could be called. If you get a dump with a long stack trace, this could be the cause. See Apache with libstdc++5 Considerations for information on how to prevent this.