# Rejecting mission request command, component or system ID mismatch **URL:** \ **Category:** MAVLink\ **Created:** [October 7, 2024, 1:46pm UTC](https://discuss.px4.io/t/rejecting-mission-request-command-component-or-system-id-mismatch/41767 "2024-10-07T13:46:07Z")\ **Posts on this page:** 8\ **Page:** 1
**Author:** ![Quincy](https://discuss.px4.io/letter_avatar_proxy/v4/letter/q/ea666f/32.png) [@Quincy](https://discuss.px4.io/u/Quincy)\ **Post date:** [October 7, 2024, 1:46pm UTC](https://discuss.px4.io/t/rejecting-mission-request-command-component-or-system-id-mismatch/41767/1 "2024-10-07T13:46:07Z")
Hi all, When performing automated flights I always receive the following vehicle error per waypoint: “Rejecting mission request command, component or system ID mismatch”. Although the error is there the drone still completes the mission. As QGC operator it is annoying to receive these errors. I traced the error down in the source code of the PX4 firmware, it relates to the mavlink\_mission.cpp file (located at: \src\modules\mavlink). However I do not understand the check that is executed to trigger this error. It seems to me that the QGC is requesting something via MAVLink which is not available. I use the following setup: - HW: PX4\_FMU\_V6X (V6X04) - Firmware PX4: 1.14.3 - QGC: 4.4.1 Any idea how this can be solved? Regards Quincy ---
**Author:** ![Alp\_Ucan](https://discuss.px4.io/user_avatar/discuss.px4.io/alp_ucan/32/22000_2.png) [@Alp\_Ucan](https://discuss.px4.io/u/Alp_Ucan)\ **Post date:** [October 7, 2024, 6:27pm UTC](https://discuss.px4.io/t/rejecting-mission-request-command-component-or-system-id-mismatch/41767/2 "2024-10-07T18:27:44Z")
Hi @Quincy. Are you sending the mission plan from QGC or you uploading the plan by using mavlink middleware like MAVSDK,MAVROS etc. ? Have you checked the **MAV\_SYS\_ID**? ---
**Author:** ![Quincy](https://discuss.px4.io/letter_avatar_proxy/v4/letter/q/ea666f/32.png) [@Quincy](https://discuss.px4.io/u/Quincy)\ **Post date:** [October 7, 2024, 6:47pm UTC](https://discuss.px4.io/t/rejecting-mission-request-command-component-or-system-id-mismatch/41767/3 "2024-10-07T18:47:37Z")
Hi @Alp_Ucan , many thanks to reach out. I make the flightplans, geofence etc. directly in QGC. I do not use any middleware. I checked MAV\_SYS\_ID in my parameter file and it is equal to “1” (default value). What does this mean wrt this error? Regards, Quincy ---
**Author:** ![Alp\_Ucan](https://discuss.px4.io/user_avatar/discuss.px4.io/alp_ucan/32/22000_2.png) [@Alp\_Ucan](https://discuss.px4.io/u/Alp_Ucan)\ **Post date:** [October 8, 2024, 8:12pm UTC](https://discuss.px4.io/t/rejecting-mission-request-command-component-or-system-id-mismatch/41767/4 "2024-10-08T20:12:55Z")
> [@Quincy](#): > > receive the following vehicle error per waypoint Because QGC sending seperate mavlink packet (MISSION\_ITEM\_INT) to vehicle for each mission item and due to ID mismatch each time it is throwing warning. > [@Quincy](#): > > What does this mean wrt this error? As far as I know QGC using MAV\_SYS\_ID and MAV\_COMP\_ID values while filling out these sections in the message default (1,1). You can check more detail about sys\_id and comp\_id from this link: [https://mavlink.io/en/services/mavlink\_id\_assignment.html](https://mavlink.io/en/services/mavlink_id_assignment.html) Interesting part is I’m using 1.14.3 too and I tried to send mavlink command and mission both from QGC and middleware app. but there is no warning. Did you try different QGC version ? I’m using 4.3.0. ---
**Author:** ![Quincy](https://discuss.px4.io/letter_avatar_proxy/v4/letter/q/ea666f/32.png) [@Quincy](https://discuss.px4.io/u/Quincy)\ **Post date:** [October 9, 2024, 11:51am UTC](https://discuss.px4.io/t/rejecting-mission-request-command-component-or-system-id-mismatch/41767/5 "2024-10-09T11:51:59Z")
The MAV\_SYS\_ID and MAV\_COMP\_ID need to be same. In my parameter file they are both equal to 1 (default value). I only use one Autopilot and one QGC station. I do not use gimballs, cameras etc. via MAVLink. I did not try another QGC version yet, I use QGC 4.4.1, do you recommend going higher or lower in versions? I will try your version anyway. On the QGC MAVLink setting page I have 255 as MAVLink system ID (default). How did you test the mission command? Did you perform a flight? Indoor I can upload the flight path and geofence without errors. In simulation the errors are not there. However the error appeared when performing outdoor flight tests, when the machine was going toward it first way point. I’m now looking how I can reproduce these errors with a machine without propellors for debugging purposes. ---
**Author:** ![Alp\_Ucan](https://discuss.px4.io/user_avatar/discuss.px4.io/alp_ucan/32/22000_2.png) [@Alp\_Ucan](https://discuss.px4.io/u/Alp_Ucan)\ **Post date:** [October 9, 2024, 8:32pm UTC](https://discuss.px4.io/t/rejecting-mission-request-command-component-or-system-id-mismatch/41767/6 "2024-10-09T20:32:16Z")
While uploading mission we were using some different way. QGC was uploading coming waypoints from a uORB topic instead of appearing ones on plan screen. This change was made in source code. And we performed many flights. I’m not sure but actually your setup is quite clear it should work without any error so I suspected new version of QGC 🤷‍♂️ If older version of QGC works please share it. Good luck. ---
**Author:** ![Quincy](https://discuss.px4.io/letter_avatar_proxy/v4/letter/q/ea666f/32.png) [@Quincy](https://discuss.px4.io/u/Quincy)\ **Post date:** [October 11, 2024, 6:44am UTC](https://discuss.px4.io/t/rejecting-mission-request-command-component-or-system-id-mismatch/41767/7 "2024-10-11T06:44:46Z")
I was able to retrieve the same errors while simulating an outdoor flight, without props on the machine. I uploaded the geofence + flight plan via QGC and launched the flight via QGC. I tested first with the latest QGC version, 4.4.2, and retrieved the errors when going (manually moving the drone) for the first way point. I then installed version 4.3.0 and performed the same test and the errors did not pop up! @Alp_Ucan , thanks for the support! Maybe something to look into for a new release of QGC? Regards, Quincy ---
**Author:** ![Alp\_Ucan](https://discuss.px4.io/user_avatar/discuss.px4.io/alp_ucan/32/22000_2.png) [@Alp\_Ucan](https://discuss.px4.io/u/Alp_Ucan)\ **Post date:** [October 11, 2024, 9:22am UTC](https://discuss.px4.io/t/rejecting-mission-request-command-component-or-system-id-mismatch/41767/8 "2024-10-11T09:22:47Z")
I examind the mavlink mission part in source code actually I would expect mission would not uploaded succesfuly while observing this warning. If I can debug to understand more detailed I will share. I don’t have enough info about QGC side but it’s look like there is an issue about mavlink packet generation. May be someone more experienced can make more accurate comment. If you can create an issue under QGC project it would be great. Have a nice day.