<p>I believe the problem is due to nested custom blocks. I tried designing a very modular program once, but it would not download at all, and I believe it's because there were too many nested blocks. However, I cannot confirm this as it seems LEGO has published little to no comprehensive information on it's software.</p>

CC BY-SA 4.0
2023-07-31T15:35:08.790Z
2023-07-31T15:35:08.790Z
Jme
<p>I can run the program perfectly in the streaming mode, but it will flash a red light in the download mode after getting 5 points. Below is my program code:</p>
<p><a href="https://i.sstatic.net/jLtJr.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/jLtJr.png" alt="program code" /></a></p>
<p>...........Updated.............</p>
<p>Finally I solved it when I delete 2 define function and group in the program start. But I don't know why it work.
<a href="https://i.sstatic.net/lyi8U.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/lyi8U.png" alt="work now" /></a></p>

<mindstorms><programming><robot-inventor>
Mindstorms program error when I play in download mode
Cat Ho
# Mindstorms program error when I play in download mode

(Asked by: username_0 on 2023-07-29)

I can run the program perfectly in the streaming mode, but it will flash a red light in the download mode after getting 5 points. Below is my program code:

[![program code](https://i.sstatic.net/jLtJr.png)](https://i.sstatic.net/jLtJr.png)

...........Updated.............

Finally I solved it when I delete 2 define function and group in the program start. But I don't know why it work.
[![work now](https://i.sstatic.net/lyi8U.png)](https://i.sstatic.net/lyi8U.png)

**Tags:** mindstorms, programming, robot-inventor


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## 1 answers

### Answer by username_1 on 2023-07-31. Score: 2

I believe the problem is due to nested custom blocks. I tried designing a very modular program once, but it would not download at all, and I believe it's because there were too many nested blocks. However, I cannot confirm this as it seems LEGO has published little to no comprehensive information on it's software.


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