What mode are you trying to use in DVDFab?
You may have to mount the image on a virtual drive for DVDFab to be able to see it.
When I used the iso image file as a source and the LG GGW-H20L as target, dvdfab just wrote the image file to disk making bvdm and certificate folders etc. It would not write it to drive
I did try to use windows file system and it made no difference, but what is interesting is when I put my bluray backup (made w/imgburn and anydvdhd) dvdfab recognized the disk and I believe would have copied and written it just fine, but the original disk it would not recognize with either the LG GGW-H20L or my new Pioneer BDR-203, I hate to have to write fentango (sp) but i think I should.
Please eloborate on mounting iso to virtual drive, I have heard this before and it should come to mind, but it doesn't (if you have the time, or I should use search and answer this myself. I just have soo much to do - my wife is getting hip replacement surgery soon and we have a million things to take care of - plus I am trying to educate myself on bluray now, since I made the leap. I thought in the past that I would never be into bluray and dismissed it as something for those who were richer than I, now I just went into debt for a new plasma tv and bluray plyer and disk drives etc and have to catch up with all the knowledge I need to go with it - should have stayed with it when it came out... oh well.
imgburn - I have only used anydvdhd and imgburn by ripping to hard drive and then writing bvdm and certificate files to drive, I have not tried the image file with it , but according to imgburn's guide there is a way to write an iso file to disk, when i try to load the folder with the bvdm and certificate folders into dvdfab it will not accept them as a source, but imgburn works very well - nice for free ware, also the write speed is higher than with dvdfab - for dvd sl and dvd dl...