Just picked up an Iconia A500 (yay $100 off coupon) and started messing with it playing games, etc.
I decided it was finally time to work, fired up adb and launched eclipse to test an app and I discovered it wasn't in my devices list. I've tried installing the acer drivers. It puts a folder in my Program Files directory...but I don't see what I'm supposed to do there. There's "EUUDriverInstaller" but when I click on it nothing (seems to) happens.
When I plug the device in it uses some generic Microsoft driver to show the device contents but composite adb doesn't show up at all like it does for my Droid.
I've reboot several times on both device and laptop. I've uninstalled / reinstalled the application that made that driver directory. I opened an application in the driver directory under the x64 folder and it opened up the windows driver installer and installed some drivers...but still no composite adb when I plug it in. It is on usb debugging and I've toggled it on and off.
It's running 3.1 stock I'm on x64 Windows 7
Both command prompt adb devices is empty under "List of devices attached" and Eclipse devices is empty. My sdk is fully updated.
I have solved the same problem by this way: connect your device, start Device Manager, find missing device driver, select update driver and browse the folder with acer drivers.