So here goes. I have host mode on my n810 working (thanks to all who posted on the subject).
The tablet detects all the flash memory drives I have thrown at it. But only after I have attached my external 2.5 hard drive (powered externally). I then get the message that says device not supported and then file manager shows my fat32 partition. I can then swap to the flash drives and back. But if I try the flash drives first, nothing happens (no device not supported message, no partition listed in file manager).

Any ideas?

By the way, I have used the search function to find out how to get host mode working in the first place and could find no mention of this problem.
I am currently using Mara's method http://www.interne.... but have had the same experience with other methods. I am using a simple A to A Female/Female adapter to physically connect the devices.
While I am happy to have it working at all, I hope to use the flash memory drives instead of the external hd as I won't always be able to power it in the field.

Thanks all, hope I was clear enough.
Cheers!