Autodesk Inventor Customization

[#1]

I have created a hole of "ISO Metric profile" with the CreateTapInfo as

oHoleTapInfo = oPartDoc.ComponentDefinition.Features.HoleFeatures.CreateTapInfo(True,  "ISO Metric profile", ""M8x1.25"", "6H", False,  "12mm")

and it is Ok.

But now I need to create a "ISO Pipe Threads" hole, and I can't find any "class" information in the "Thread.xls",

when I set CreateTapInfo as 

oHoleTapInfo = oPartDoc.ComponentDefinition.Features.HoleFeatures.CreateTapInfo(True,  "ISO Pipe Threads", HSize, " ", False, b & "mm")

the error occur.

How to set the class information of "ISO Pipe Threads"?

Thanks a lot for your help!

[#2]

The CreateTapInfo I setted is 

oHoleTapInfo = oPartDoc.ComponentDefinition.Features.HoleFeatures.CreateTapInfo(True, "ISO Pipe Threads", "G 1/8", " ", False,"10mm")

thanks