As the title mentioned I have the following problem: I use Eclipse with Maven Nature and when I update my Maven Project, I get this error:
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
This issue (https://bugs.eclipse.org/394042) is fixed in m2e 1.5.0 which is available for Eclipse Kepler and Luna from this p2 repo :
http://download.eclipse.org/technology/m2e/releases/1.5
If you also use m2e-wtp, you'll need to install m2e-wtp 1.1.0 as well :
http://download.eclipse.org/m2e-wtp/releases/luna/1.1
I have that problem and my solution is going source folder and run command line: mvn clean install -DskipTests eclipse:eclipse then return eclipse workspace and refresh project. Hope that help!
This is all you need:
Right-click on your project, select Maven -> Remove Maven Nature.
Open you terminal, navgate to your project folder and run mvn eclipse:clean
Right click on your Project and select Configure -> Convert into Maven Project
Right click on your Project and select Maven -> Update Project
I had to do it slightly different to work for me:
mvn eclipse:clean (with project open in eclipse/STS)I imported the project as general project from git repository.
.settings, .project and  .classpath in project's folder Configure -> Convert to Maven Project. Only this solved the problem in my case.