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

Solution 1:

I had to do it slightly different to work for me:

1. rightclick project, remove maven nature (or in newer eclipse, "Maven->Disable Maven Nature")
2. mvn eclipse:clean (with project open in eclipse/STS)
3. delete the project in eclipse (but do not delete the sources)
4. Import existing Maven project

Solution 2:

• I just went to Properties -> Java Build Path -> Libraries and removed the blue entries starting with M2_REPO.

• After that, I could use Maven -> Update Project again

Solution 3:

This is all you need:

1. Right-click on your project, select Maven -> Remove Maven Nature.

2. Open you terminal, navgate to your project folder and run mvn eclipse:clean

3. Right click on your Project and select Configure -> Convert into Maven Project

4. Right click on your Project and select Maven -> Update Project