Update.....
error code 0xFFFFD8F1...
Some more checking on dijonstock turned up some information....
My 4416's screen HD error code wrote:
CAN NOT FIND HHD
ERROR !!!! CODE : 0XFFFFD8F1
DO YOU START UP MIXER SECTION ONLY ? [Y(ANY)]
Is this the screen you see ?
If so the HD is indeed corrupted and it's removal and connection to a PC is warranted for a reformat so the 4416 will see it again. Because is is an IDE hard drive a PC will see it with the proper cableing. More than likely it is a Travelstar notebook HD. This is something any PC service center can do for you. The HD is easily removed from the caddy once it is removed from your 4416's HD slot with the two thumbscrews provided. The down side of this is that all data will be lost during the reformat except the operating system which is contained in the memory. Once it "see's " the drive correctly , it may ask you to let the 4416 format it again , so in this case you would say YES and allow it. Then the recorder will be usable again.
If you can get a PC to "see" it without formatting , then do a defrag within the PC and then reinstall it and try again.
Outside of the box you might just try sliding the caddy back and reinstalling it by using finger power instead of the thumbscrews. It's easier to feel the connector engage that way. Also make sure HD mounting board is BETWEEN the two ridges on EACH side of the bay. Check this visually. You may just not have the HD caddy plugged in well.
Hope this helps.
msg
I will proceed from here and hopefully I will find success..
I'm quite competent when it comes to taking apart the Roland 808ex's but I've never had the nerve to open up the AW2816.