Eclipse JUnit - possible causes of seeing “initializationError” in Eclipse window

Question

I know this question is pretty general but I haven\'t found any hints on why this error may show up. What are possible causes of seeing initalizationError in Eclips

Answer 1

I had naively added junit-4.12.jar from poi.apache.org to my Build Path in Eclipse. I deleted it (Project, Properties, Java Build Path, Libraries, junit-4.12.jar, Remove) then in my test class allowed Eclipse to "Fix Project Setup" after pressing Ctrl-1. No more problems! :-)