API Documentation > SOAP API > InterFAX High Availability SOAP API InterFAX High Availability SOAP API InterFAX High Availability SOAP API Service Endpoint SOAP Method Reference SendCharFax (HA) SendFax (HA) SendFaxEX_3 (HA) CancelFax (HA) SendChainedFax (HA) QueryCompleted (HA) QueryList (HA) Helper Methods GetAllErrorCodes(HA) GetErrorDescription(HA) GetSupportedFileTypes(HA) IsSupportedFileType(HA) Appendix A: Return Codes Appendix B: Special Formats Appendix C: InterFAX Status Codes Supported File Types High Availability Service – System Limitations