hair render problem

Lampace

it becomes white and grey as in no texture at all in iray now, basicly happened to the new hair products, old ones render fine, i know i can fix this by applying uber base shader, but still different from vendor's default setting and this is so strange, cause they do look normal just a few days back, i noticed that there's no "base mixing" option anymore every time load the hair or apply base material (OOT's), i've already tried resintalling DAZ (4.9.3) and product files, please help me, any suggestions are welcome, thank you! 

below is OOT's georgia hair (nothing wrong with the product itself),  they all look normal in viewport, and i think it only has sth. to do with the shader setting...

lwaves

I'm not sure what exactly you are doing but this works for Georgia and others like it:
Load the hair - Select the hair in the scene - Select the hair surfaces - Apply the Hair Base Material from the Iray materials folder (it says 'Apply First' in big red letters and makes everything white) - Apply the colour material that you require.
It renders fine after that. Are you trying to apply the base mat after the colour? If this hair previously worked for you maybe some files accidently got moved or deleted but then you state that you did a reinstall. Top Tip: Don't bother reinstalling the full program for something like this, you're just wasting time as it rarely is the software. Reinstalling the affected product is fine though.

Can you post a screenshot of your Iray materials content folder (the one in the DS Content Library) if you still have trouble.