Connectivity issues between DevTest and SAP can have multiple causes. This document describes the most common ones, encountered in PoCs and tests.Note: In DevTest versions prior to 10.2, DevTest VSE and DevTest workstation did not release SAP JCo resources correctly that were bound to an even failed connection to the SAP system. Not even starting and stopping the virtual SAP IDoc service, nor redeployment of the virtual SAP service released these resources. If any of the connectivity issues occurred in versions prior to DevTest 10.2, please follow the procedure described in section 'Restart DevTest SAP JCo Environment'.