error importing " import org.eclipse.wb.swt.SWTResourceManager;"

Dear users,

I am trying to import a project I made on another computer using windowbuilder.
Now it's giving me an error on "import org.eclipse.wb.swt.SWTResourceManager;" that it cannot be resolved

Can someone help me?

btw I'm using eclipse and all windowbuilder plugins are also installed on this computer

add the jar containing the SWTResourceManager to your classpath.