# Loading program issue on WAGO 750-832 and 750-881 controllers **URL:** \ **Category:** Hardware and Linux\ **Tags:** how-to\ **Created:** [May 5, 2026, 9:33pm UTC](https://www.wago.community/t/probleme-de-chargement-programme-sur-controleurs-wago-750-832-et-750-881/2716 "2026-05-05T21:33:09Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![Albert](https://avatars.discourse-cdn.com/v4/letter/a/48db29/32.png) [@Albert](https://www.wago.community/u/Albert)\ **Post date:** [May 5, 2026, 9:33pm UTC](https://www.wago.community/t/probleme-de-chargement-programme-sur-controleurs-wago-750-832-et-750-881/2716/1 "2026-05-05T21:33:09Z")
Hello, I replaced a WAGO 750-832 controller. When I reach the step (Online → Create Initialization Project), an error message appears (see attachment), and then the I/O LED either does not light up or flashes red, followed by “Communication Fault (#0): Logout”. I even tested an old WAGO 750-881 controller that I believe is out of service. When I reach the step (Online → Create Initialization Project), an error message appears (see attachment), and then all LEDs start flashing red, followed by “Communication Fault (#0): Logout”. ![Screenshot 2026-05-05 165252](https://us1.discourse-cdn.com/flex016/uploads/wago/original/2X/8/8eee236617a88622d6167ae7cfa0a707da675f52.png) Here are the steps I followed for loading: 1. Changing the target configuration (selector position **in the middle** ) → **OK** 2. Checking the program (Project → Compile All) (selector position **in the middle** ) → **OK** 3. Loading the program (Online → Access System → Start) (selector position **in the middle** ) → **OK** 4. Loading the program at startup (Online → Create Initialization Project) (selector position **in the middle** ) → **NOK** 5. Loading the program into internal memory (Online → Downloaded application from source code to PLC) → **step not reached** Can you help me find a solution to load the program correctly? Do you think the WAGO 750-881 controller is actually out of service? Thank you. ---
**Author:** ![Albert](https://avatars.discourse-cdn.com/v4/letter/a/48db29/32.png) [@Albert](https://www.wago.community/u/Albert)\ **Post date:** [May 6, 2026, 9:11pm UTC](https://www.wago.community/t/probleme-de-chargement-programme-sur-controleurs-wago-750-832-et-750-881/2716/2 "2026-05-06T21:11:31Z")
750-832: flashing code 6-10 ---
**Author:** ![WagoIcard](https://sea2.discourse-cdn.com/flex016/user_avatar/www.wago.community/wagoicard/32/1508_2.png) [@WagoIcard](https://www.wago.community/u/WagoIcard)\ **Post date:** [May 7, 2026, 1:10am UTC](https://www.wago.community/t/probleme-de-chargement-programme-sur-controleurs-wago-750-832-et-750-881/2716/3 "2026-05-07T01:10:59Z")
Hello, First, in your program are you sure there is not an infinite loop somewhere ? Something you can do is to change your task priority for something higher than 11 (Background task). this will allow the ethernet communication to not be interrupted by the program. Next the error 6-10 is a BACnet configuration error. Have you set the SYM-XML settings for the BACnet export ? When you ask for a download, do you have a BACnet upload request popup ? ---
**Author:** ![Albert](https://avatars.discourse-cdn.com/v4/letter/a/48db29/32.png) [@Albert](https://www.wago.community/u/Albert)\ **Post date:** [May 7, 2026, 9:02am UTC](https://www.wago.community/t/probleme-de-chargement-programme-sur-controleurs-wago-750-832-et-750-881/2716/4 "2026-05-07T09:02:26Z")
Hello, No, I do not have an infinite loop. The program was working fine before with the old PLC. Regarding the modification priority, could you please provide the steps? The SYM-XML parameters for BACnet export are configured; I followed the steps in the 750-832 manual. I have a 753-648 module: the LED on G is blinking red and the LED on C is blinking green. When I start a download, a pop-up window appears asking to update the BACnet objects on the target. The software is CoDeSys 2.3.9.68. Thank you. ---
**Author:** ![WagoIcard](https://sea2.discourse-cdn.com/flex016/user_avatar/www.wago.community/wagoicard/32/1508_2.png) [@WagoIcard](https://www.wago.community/u/WagoIcard)\ **Post date:** [May 7, 2026, 9:27am UTC](https://www.wago.community/t/probleme-de-chargement-programme-sur-controleurs-wago-750-832-et-750-881/2716/5 "2026-05-07T09:27:00Z")
The old PLC is a BACnet controller too ? In [Project] \> [Option], in the menu [Symbol Configuration]. ![image](https://us1.discourse-cdn.com/flex016/uploads/wago/original/2X/5/5c956788dd74950f87720b01cda2ec81737822d8.png) Check both case then open the [Configure symbol file], Select everything, uncheck all cases starting from the bottom: ![image](https://us1.discourse-cdn.com/flex016/uploads/wago/original/2X/2/273d11822d3142c566f23041e043e9b0cb888037.png) Select what object you want to be available to the BACnet configurator and check only the 2 top checkboxes: ![image](https://us1.discourse-cdn.com/flex016/uploads/wago/original/2X/4/4c2d409081cdae54fc5c27c08f45c91c152f1dae.png) and it should be good to go. Ps don’t forget to Create the boot project, if I remember right the PLC will reboot after you disconnect to update the BACnet system automatically. ---
**Author:** ![Albert](https://avatars.discourse-cdn.com/v4/letter/a/48db29/32.png) [@Albert](https://www.wago.community/u/Albert)\ **Post date:** [May 7, 2026, 9:56am UTC](https://www.wago.community/t/probleme-de-chargement-programme-sur-controleurs-wago-750-832-et-750-881/2716/6 "2026-05-07T09:56:10Z")
Thank you But when I switch the selector to RUN mode, the I/O LED is off