Hi Pavel,
If your addon takes more than a certain amount of time to complete, it will automatically get disconnected by the UI server and result in that kind of error.
If your add-on needs to do heavy work in handler procedure of an SAP Business One event, we recommend that you call this method per minute. Otherwise, you might get errors like "System call failed. (Exception from HRESULT: 0x80010100 (RPC_E_SYS_CALL_FAILED))". This may occurs on a non-server edition Windows system (for example, Windows 7 and Windows XP) due to the post message limit of the Windows system.
You can use the SBO_Application.RemoveWindowsMessage(SAPbouiCOM.BoWindowsMessageType.bo_WM_TIMER, true);
to prevent the issue.
Best regards,
Pedro Magueija
