It seems like there could be a few different reasons for the errors you're seeing. Here are a couple of common troubleshooting steps you can try:
1. Check for any typos or errors in your code. Make sure all syntax is correct and there are no missing or extra characters.
2. Ensure you have added all the necessary references and dependencies to your project.
3. Try cleaning your solution and rebuilding it again.
If you continue to encounter issues, providing more specific details about the errors you're seeing can help us give you more targeted advice.