Palette not displaying in Webform integration

I just got the same error on webform 3.19 installed into Drupal Commons 3.2.

I had it working on another Drupal Commons site with 3.18, so I uninstalled and went back to webform 3.18, but the issue is still there.

I am getting is this warning:

Notice: Constant FORM_BUILDER_ROOT already defined in require_once() (line 8 of [drupal-root]/sites/all/modules/contrib/form_builder/form_builder.module).

so I am wondering if there is some conflict happening? Any advice on where to look?

Don't know if this will help anyone, but I recently debugged an issue with missing palette on a client site...

The problem was that form builder will not display the palette if it thinks the form builder palette block has been activated. On the blocks UI for the seven theme we couldn't even see the form builder palette block listed, but it was set to status=1 in the database!

So we did UPDATE block SET status=0 WHERE module='form_builder'; to disable it for all themes, and the palette appeared again.

@grahamC, Thanks! ... I think I have a different problem.

If I try to add the form_builder fields block manually to the page the block is completely missing (as in screen shot in summary), if I run your db update the block is there but it's empty, as if I had every field turned off.

Thanks grahamC. Your solution worked for me.

Special thanks to grahamC for a wonderful working patch !

Thanks grahamC.

Your solution worked for me too.