Great Ozzy, many thanks, you are always gentle.
I don't know the code so is not always simple to understand some things releated to this.
In the end after some checks it doesn't seems to be a noidex problem, but I have noted with a developer is helping me that on my forum some nodes have all the threads inside without the h1 tag but some other has and we are not understanding why.
We have also checked the robots permissions inside the node and is setted in the same way in both nodes so we aren't understanding what and where is the problem. It's really stang that. Have you some idea?
Thanks again