I'm going to ask you to post some additional information that might help us to identify the problem.
Please do this:
- Select File > Preferences from the Arduino IDE's menus.
- Check the box next to "Show verbose output during: [] compilation".
- Click the OK button.
- Select Sketch > Verify/Compile from the Arduino IDE's menus.
- Wait for the compilation to end.
- Right click on the black "Output" pane at the bottom of the Arduino IDE 2.x window.
- From the context menu, click Copy All.
- Open a forum reply here by clicking the Reply button.
- Click the
</>icon on the post composer toolbar. This will add the forum's code block markup (```) to your reply to make sure the error messages are correctly formatted.
- Press Ctrl+V. This will paste the compilation output into the code block.
- Move the cursor outside of the code tags before you add any additional text to your reply.
- Click the Reply button to post the output.