I'm running Houdini Apprentice 9.5.379 64 bit version, under Vista 64 SP1.
This is running on a MacPro 8 core, 6GB RAM, Nvidia 8800 GT

About an hour or or two ago I started to get various Houdini Console errors like this:

“No licenses could be found to run this application.
Please check for a valid license server host”

If I go to the License Administrator it seems to think everything is OK. Currently it seems as if this is triggered when I go to render. If I run the main Houdini program I don't get this error. Sometimes when I I type stuff in the help page in the browser, this, or errors similar to it, are triggered in the Console.

Anything I can do about this?

Since the license error occurs only when you render, perhaps you are trying to run two render jobs at the same time. Free Apperntice comes with only one license token for Mantra rendering, and, unlike licenses for Houdini, the Mantra license tokens are per CPU core, which means that if a second Mantra runs on a second core, a license is required. Thus up to 8 render tokens may be required on your machine.

http://www.sidefx.com/index.php?option=com_content&task=view&id=1206&Itemid=273#mantra [sidefx.com]

Well I checked, and as far as I can tell I'm only rendering one job. I'm just clicking the render button on UI, which then brings up the mplay window/process. I'll see if it happens again tonight. Last night it was intermittent, shortly after I posted this topic it stopped for a while, then came back after an hour or so.