Hey thanks for the heads up Boston Kiwi
I am using Adobe Acrobat 9 Standard, and this problem occured after updating to 9.3.1.. I purchased a registry cleaner to no avail, as that was a suggested solution I'd come accross..
So I call adobe... They insist that Adobe Acrobat 9 Standard does not support the 3D feature. And no support is provided for the reader whatsoever. Adobe support suggested I uninstall/reinstall the software. I did this, and was able to open the Microstation generated 3D PDF file.. UNTIL (the idiot I am) I ran the update... upon which the error returned.
Adobe still says that the Standard addition does not support 3D.. So their solution is A. Buy Proffesional, B: DO NOT INSTALL UPDATE... So I have mailed out IT dept, and informed them to get the info out ton NOT do the 93.1 update!! Kind of a sorry response from Adobe in my opinion..
So.. I came accross your suggestion here, wit hcahnging the print settings in Microstation... and it worked for me too happily.. I guess now I should direct my frustration at Bentley instead of Adobe..lol
Thanks Mate..
Hans