I downloaded Houdini Apprentice 10 and started to use it. Everything was fine until I downloaded and installed Internet Explorer 8. Now I get the following error message:

Unable to connect to hserver for licence acquisition.

I am currently running Houdini on Dell laptop using 32 bit Windows Vista. I went to Services through the Control Panel and found HoudiniServer. I located hserver.exe in C:\Windows\system32.

I launched the Houdini License Administrator. The valid licenses seem to be installed. According to that program, the license server is running and is allowed to serve licenses. The license server allows license modifications from my laptop.

Not sure what the problem is. Any suggestions?

The error message suggests that Houdini cannot make a TCP/IP connection to the HoudiniServer (hserver) service. But if this service is running, then maybe it is a firewall or some security setting that prevents the connection from being made. So try playing with the permissions and the firewall.

You can also try turning on the “Standalone Mode” in License Administrator's File > Change Server dialog box. This will tell Houdini to use interprocess communication rather than TCP/IP on Windows.

You can also reconfigure Houdini to use Local Licensing, which makes Houdini verify the license itself. This bypasses hserver and sesinetd services altogether.
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