External HDD constantly flashing while there is nothing in queue. Apps or games not...

1, Attempt to retry the install from the Install Queue

2. Users still seeing a corruption error should try to uninstall/reinstall HW2

3. If you are still experiencing an issue and you have an external HDD, one of the below options should be attempted:

--Try to install to the external HDD

--Copy other games and apps to the external HDD, factory reset the console, and then reinstall HW2

4. If the game was installed to an external HDD, make room on the internal HDD by moving things from the internal

XA- Austin

Well i've got an answer from Ubisoft support. The game MUST be installed into the original xbox HDD.

Any external device wont work, either an external HDD or an flash USB. both wont work, only original XBOX HDD

An important note is not so much the size of the HDD but that the 4Gb is a Flash Drive. Some Games Features will not work via the 4Gb Flash Drive and require the use of a HDD. Adding an External Drive (Flash or not) will also
not work for those Features.

It will vary Game per Game and it will be stated on the Games box if a HDD is required. Other than that, it's just storage space for Installing Games (completely Optional for most Games with exceptions). As noted some Games (such as BF3/ BF4 and such) will
require a HDD (will not work from the 4Gb Flash Drive).

Try unplugging your external hdd or flash drives during the update.

It could simply be the flash drives themselves. As I understand it, flash drives are notoriously unreliable. I would suggest trying an official Xbox HDD. You can also get an external HDD up to 2TB in size running USB 3.0 (the console will accept two of these).
I'm using an official 500GB HDD and I Western Digital 2TB external HDD with no problems. The reason why I suggest the official drive is that some games will require it for installation or download.