TP_IDs and CONV_Ids cannot be shared across Windows processes

This article was previously published under Q152012

When you use the SNA Server 16-bit or 32-bit Windows APPC interface, the APPC transaction program ID (TP_ID) and conversation ID (CONV_ID) parameters are only valid from the Windows process (or task) that created them. For example, if a 16-bit Windows APPC application receives a TP_ID by calling TP_STARTED, and a CONV_ID by calling [MC_]ALLOCATE, the TP_ID and CONV_ID are invalid if used by a different 16-bit Windows process. If another process tries to use these parameters when calling the APPC interface, the following APPC errors will occur: SNA Server 32-bit Windows applications that call TP_STARTED and [MC_]ALLOCATE may appear to receive the same TP_ID and CONV_ID values. However, the underlying SNA Server APPC interface recognizes these values as unique because they are created by different process IDs.