Hello
hammy
October 7, 2025, 7:25pm
2
Which device are you trying to upload too ?
Have you the board manager for that board installed ?
Do you maybe use the latest (2.8.1) version of the stm32duino core?
That does not support the V1 IDE (1.8.19) anymore. I had to rollback to V 2.7.1 as the V2.8.1 also made all my COM ports go away. Even for other boards than STM.
Try restarting the IDE and your computer. I have had similar problems on my Arduino IDE running on Linux.
Hi @esp8266mod_56 . Do you have the "esp32 " boards platform installed?
There is a bug in version 3.3.1 of that platform which causes Arduino IDE 1.x to not recognize serial ports:
opened 04:45PM - 01 Oct 25 UTC
closed 07:39PM - 01 Oct 25 UTC
Status: Awaiting triage
### Board
any
### Device Description
n.a.
### Hardware Configuration
n.a.
…
### Version
v3.3.1
### Type
Bug
### IDE Name
Arduino IDE 1.8.9
### Operating System
Kubuntu Linux 24.04, Kernel 6.8.0-85 (latest)
### Flash frequency
n.a.
### PSRAM enabled
no
### Upload speed
n.a.
### Description
In Arduino IDE 1.8.9 after upgrade to arduino-esp32 v3.3.1 and restart of Arduino IDE serial port no longer is available (grayed out). After downgrade to arduino-esp32 v3.3.0 (and restart of IDE) port is available again, same for version 3.2.1.
In Arduino IDE 2.3.6 serial port works with arduino-esp32 v3.3.1
Starting Arduino IDE from console with arduino-esp32 v3.3.1 shows following exception:
Exception in thread "cc.arduino.packages.discoverers.serial.SerialDiscovery" java.lang.IndexOutOfBoundsException: Index: 2, Size: 2
at java.util.LinkedList.checkElementIndex(LinkedList.java:555)
at java.util.LinkedList.get(LinkedList.java:476)
at processing.app.Platform.resolveDeviceByVendorIdProductId(Platform.java:188)
at cc.arduino.packages.discoverers.serial.SerialDiscovery.forceRefresh(SerialDiscovery.java:166)
at cc.arduino.packages.discoverers.serial.SerialDiscovery$1.run(SerialDiscovery.java:96)
at java.util.TimerThread.mainLoop(Timer.java:555)
at java.util.TimerThread.run(Timer.java:505)
### Sketch
```cpp
n.a.
```
### Debug Message
```plain
n.a.
```
### Other Steps to Reproduce
_No response_
### I have checked existing issues, online documentation and the Troubleshooting Guide
- [x] I confirm I have checked existing issues, online documentation and Troubleshooting guide.
This is the same type of bug that @hmeijdam mentioned in the "STM32 MCU based boards " platform , but that bug was actually fixed some time ago , so it would only affect users who have an outdated version of the STM32 MCU based boards platform installed.
My page here explores a lot of these issues and describes some apps that are useful for resolving connection issues.
