My Samsung Galaxy Gio (S5660) is unable to connect to any computer (already tried on 4, all with kies, other cables, etc). It always says unrecognized device, even on downloading mode. It is on stock gingerbread, but it was on CM 7.2, i remember i flashed a ext4formatter.zip on the procedure.
Already tried USB Debugging and Unknown Resources, reinstalled Kies, and even installed Samsung USB Driver for Mobile Phones
In my opinion it seems to be about the phone. Even when trying to install a official update from samsung the installation fails with a 0x80010093 error code.
Doesn't ext4/rts have nothing to do with this?
I have seen that message "unrecognized device" on older PCs with only USB 1.1 ports on it (using printers, scanner, memory sticks, etc not mobile phones).
If your PC is a newer model then I have no idea.
Try to connect it on a friends PC (preferably a new PC, or on as many PCs as possible) so you may find that the faulty device is the phone or the PC.