The following table shows which of the event interfaces can be called in each of the Microsoft Exchange contexts.
| Context | Interfaces |
|---|---|
| EECONTEXT_TASK | IExchExt::Install IUnknown::Release |
| EECONTEXT_SESSION | IExchExt IExchExtSessionEvents |
| EECONTEXT_VIEWER EECONTEXT_REMOTEVIEWER EECONTEXT_SEARCHVIEWER | IExchExt IExchExtCommands IExchExtUserEvents IExchExtPropertySheets |
| EECONTEXT_ADDRBOOK | IExchExt IExchExtCommands IExchExtUserEvents IExchExtPropertySheets |
| EECONTEXT_SENDNOTEMESSAGE EECONTEXT_READNOTEMESSAGE EECONTEXT_READREPORTMESSAGE EECONTEXT_SENDRESENDMESSAGE EECONTEXT_READPOSTMESSAGE EECONTEXT_SENDPOSTMESSAGE | IExchExt IExchExtCommands IExchExtUserEvents IExchExtMessageEvents IExchExtAttachedFileEvents IExchExtPropertySheets |
| EECONTEXT_PROPERTYSHEETS | IExchExt IExchExtPropertySheets |
| EECONTEXT_ADVANCEDCRITERIA | IExchExt IExchExtAdvancedCriteria |