'Building workspace' has encountered an error

Question

Eclipse Luna 4.4.0

Error occurred during the Build

Error instantiating builder 'ord.eclipse.m2e.core.maven2Builder'.
Plug-in org.eclipse.m2e.core was unable to load class org.eclipse.m2e.core.internal.builder.MavenBuilder
An error occurred while automatically activating bundle org.eclipse.m2e.core (547).
Plug-in org.eclipse.m2e.core was unable to load class org.eclipse.m2e.core.internal.builder.MavenBuilder.
An error occurred while automatically activating bundle org.eclipse.m2e.core (547).
Error instantiating builder 'org.eclipse.m2e.core.maven2Builder'.
Plug-in org.eclipse.m2e.core was unable to load class org.eclipse.m2e.core.internal.builder.MavenBuilder.
An error occurred while automatically activating bundle org.eclipse.m23.core (547).
Plug-in org.eclipse.m2e.core was unable to load class org.eclipse.m2e.core.internal.builder.MavenBuilder.
an error occurred while automatically activating bundle org.eclipse.m2e.core (547).

if i delete the folder .metadata and all .project and .setting data from my workspace, i get no error. After one day of work i´ll get the same error.

Answer 1

Try next steps:

1. Go to your eclipse installation folder
2. Run "eclipse.exe -clean"
3. Work normally
4. Enjoy

Answer 2

I ran into this same issue and I believe the culprit to be the Sonarqube plugin I had installed.

This discussion pointed me in that direction:

http://forum.spring.io/forum/spring-projects/springsource-tool-suite/749864-sts-ggts-3-6-0-m1-released

Uninstalled the Sonarqube plugin and the error is gone.