Personal Communications Response

Personal Communications returns the list of DDE topics in CF_TEXT format in a DDE DATA message. 
WM_DDE_DATA(hData, aTOPICS)
The following topics are supported by Personal Communications:
  • System – System Topic
  • SessionA – Session A Topic

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  • SessionZ – Session Z Topic
Note:
The actual number of session topics supported depends on the number of sessions currently opened. The client program should always query the topics data item of the system topic to obtain the list of sessions currently opened.
If Personal Communications cannot return the list of topics, a DDE ACK message is returned with an error code in the low-order byte of the wStatus word: 
WM_DDE_ACK(wStatus, aTOPICS)
Return Code Explanation
9 A system error occurred.