Maven Eclipse Error - Unsupported IClasspathEntry / Nullpointer

Error message box appears while importing maven project having message:


An internal error occurred during: "Updating Maven Project".
Unsupported IClasspathEntry kind=4

Solution: 

1. Right-click on your project, select Maven -> Remove Maven Nature.
2. Open you terminal, go to your project folder and do “mvn eclipse:clean”. (NOTE: You will get error in the eclipse IDE for missing files. But, donot worry about that. It will be resolved after next step)
3. Right click on your Project and select “Configure -> Convert into Maven Project”

Result: 

Main error about classpath entry will be resolved.