Hello @linchenji ,
Thanks for your post.
The issue is very likely related to extension activation performance. MCUXpresso extension performs environment scanning and initialization during startup, which can occasionally be delayed due to workspace size, SDK path access, or toolchain dependencies.
Suggested actions:
1. Use a lightweight workspace (avoid opening full SDK directory)
2. Check extension logs for activation delay
You can access the logs via:
View → Output → select “MCUXpresso for VS Code” or “Extension Host”, and check if there are any abnormal log entries.

3. Update VS Code and MCUXpresso extension to latest version
Hope it helps.
BR
Celeste