Eclipse error: This project needs to migrate WTP metadata

The above solution works fine but it creeps up again and again. An easier solution is to right click on the concerned project in Eclipse and choose Validate.

For me, none of these worked. The solution for me was deleting the following file while Eclipse was stopped:

/workspace/.metadata/.plugins/org.eclipse.core.resources/.projects/myprojectname/.markers

Here is another thing you could try, only this worked for me :(

Go to project properties > Project facets > there tick "Java" and "Utility Module" ... apply This works if your project is referenced from other projects ..otherwise you could play with those options ...see which one works for you.

try adding this line in the .project file

<nature>org.eclipse.wst.common.project.facet.core.nature</nature>

Or refer to this discussion: for instance, make sure there is no duplicate entries in .sessions/org.eclipse.wst.common.component

As noted in the comment by larf311, the actual answer in this instance was:

delete the ".settings/org.eclipse.wst.common.component" file.

Simple. ;)