Eclipse error occurred during Repository registry initialization

Question

I suddenly encountered an error initializing Eclipse Kepler:

An internal error occurred during: "Repository registry initialization". For input string: "(pilgrim's conflicted copy 2013-10-18).gen" 

Answer 1

I found it!!!

Delete the directories inside:

.metadata/.plugins/org.eclipse.m2e.core/nexus/ 

And rebuild the maven project.

Note: this also applies to Eclipse Luna.