GI Irradiance Cache file

Hello...
i really have a big problem , in my render settings at global illumination filed is missing the irradiance cache file ...
can anyone tell me why ?
I'm looking for this because as many cinema 4d users i met this message :
"GI irradiance cache file cannot be written -please check output path "
i've read that the problem could be on Global Illumination ->Irradiance Cache File , but Irradiance Cache File doesn't exist either .

I will be grateful if anyone could help me !
Thank you .

http://screencast.com/t/ZDJlZWUzY

Hi men Y from argentina y habe de solution, you nid put in de option
Global illumination=

Irradiance Cache File (Custom Location) and Select sam folder in (location).
Nathin more good luck