linear temperature as a load on nodes

Hi everyone,

I'm conducting coupled thermal/structural stress analysis using Optistruct. As structural loads, I have spcs (load collector:spc) and a rotational force (load collector:rotation using RFORCE as card image).As a thermal load I've linear temperature on the nodes belonging to one surface. For the thermal stress analysis, I've created another load collector named 'temperature' and then I've defined on the nodes linear temperature using the temperatures panel. The load type was set to TEMP according to tutorial OS-1100: Thermal Stress Analysis of a Printed Circuit Board with Anisotropic Material Properties. Then for the load step, I'm creating a single load step using analysis type 'linear static' defining the spcs and loads(rotation) and in the TEMP section I'm choosing 'temperatures' from the load collectors. However I become the following error: *** ERROR # 4800 *** Grid 15361 connected to element 44763 has no temperature specified in load set 3. To apply zero temperature on this grid, SYSSETTING,undeftemp,zero needs to be added to the deck. Can anyone help me solving this problem?

Best Regards

Mert