The project XXX does not have any GWT SDKs on its build path

Question

Sometimes, when I start Eclipse (Java EE IDE for Web Developers, Indigo SR 1) on my MacOSX Lion, my GWT (2.4.0) project initially fails to compile.

Eclipse displays the following message in the "Problems" section:

The project XXX does not have any GWT SDKs on its build path 

Here is a list of semi-solutions that sometimes work (I normally try them in this order):

1. Project > Clean.
2. Remove and re-add GWT SDK to the build path.
3. Restart the machine.

Any help with preventing the problem from re-occurring would be most welcome.

Answer 1

I encountered the same problems as described above. But none of the solutions worked.

What did work was moving the GWT SDK above the other GWT dependencies in the build path. See the following blog (written by my personal hero of the day): Grant Little's Blog

Answer 2

I believe the problem was occurring because Eclipse had some stale settings about available/linked GWTs.

Therefore, building on the answer by Chris Cashwell, I recommend the following:

1. Remove all GWTs from your build path. (You might have more than one GWT on your build path.)
2. Remove all GWTs linked in Eclipse in Project>Properties>Google>Web Toolkit>Configure SDKs, .
3. Add only the latest GWT, and make it default.

EDIT: Sometimes, I still need to do a Project > Clean, but this is rare now.