Eclipse: The declared package does not match the expected package

Question

I have a problem importing an external project. I go File -> Import... -> Existing Projects into Workspace, choose the folder where the project is located and everything is

Answer 1

1. Right click on the external folder which is having package

src.prefix1.prefix.packagename1 
src.prefix1.prefix.packagename2

2. Click Build path --> Remove from build path.

3. Now go the folder prefix1 in the folder section of your project.

4. Right click on it --> Build path --> Use as source folder.

5. Done. The package folder wont show any error now. If it still shows, just restart the project.