How do I troubleshoot when developing with the SOAP API?

Environment:

Connect Web Services for SOAP (CWS) API, All Versions

Resolution:

Please refer to product documentation specific to "Connect Web Services for SOAP (Connect Web Services)" for up-to-date information on this product feature.  This information is accessible from the following answer:

Answer ID 5169: Technical Documentation and Sample Code

Further, information specific to establishing and troubleshooting connections with the SOAP API can be found using the following answers:

Answer ID 4832: Connect Web Services for SOAP access

Answer ID 6741: Correct Syntax for connecting through the wsdl

Answer ID 5318: SOAP API security

Answer ID 6756: Access Denied with SOAP API

If an issue with the SOAP API is suspected please submit a service request via Ask Technical Support. The following answer describes what is needed by Support when performing a defect investigation involving the SOAP API:

Answer ID 6499: Working with Support on troubleshooting SOAP issues