I am getting this error when installing EGit:
Cannot complete the install because one or more required items could not be found. Software being in
The "EGit Import Support" feature requires Eclipse 3.8, 4.2 or higher. Just deselect the checkbox, and installing should work.
See here about the feature: http://wiki.eclipse.org/EGit/New_and_Noteworthy/2.0#Support_for_Eclipse-SourceReferences_manifest_headers