I have a question I had my controller almost three years with no problems updated controller to 1.5.2 and all hell broke loose it’s corrupting all my songs I never had an issue with corruption before now my controller won’t upload any music without giving me a corruption notification and it won’t let me use serato either do I need to send my controller to the shop and I mean I’m confused what should I do because I can’t even use the controller no more now
I assume that database recovery failed. I feel your desperation. I was also a victim of a database error. I couldn’t solve the problem and I decided to rename the database on the hard disk and not delete it (yet). I then built a new database of music. This worked and I then started supplementing the database with music. Since 2 years I have not seen any reports from a corupte database. I still don’t know exactly what went wrong, but I think it had to do with connecting and disconnecting external hard drives, USB sticks, etc., or disconnecting the power supply prematurely. So you have to pay attention to that because this could be the reason for this problem. If you follow my advice, I wish you luck. I got rid of the problem and gained a lot of experience with it. Incidentally, I never used that corrupt database again and later removed it from my PC.
Okay so I have an hard drive inside my controller so you saying rename the hard drive cuz it’s labeled as prime so I should change the name of it and that’s just solve the problem? I had to do that to some of my folders I didn’t think of that
Where in his text does he state that?
He renamed the Engine folder (or affected .db files) to start over.
I meant as Reese puts it. Rename or delete your database on the hard disk of the PC / Laptop. And start building your database again and then watch out for removing devices. Do not do it. If things go wrong there, I believe the database will be irreparably destroyed.
I’m trying it now so far it’s working we’ll see when I come across a file that crashes the system again… 
Thank you for the confidence shown. 
I’ve updated EP to 1.6 version and still not working properly. The corrupt database warning is still showing. Pease help.
Can someone here please share the 1.6 beta firmware for P4. The latest 1.6 release is giving me this “corrupt database” problem that I never had before with the beta. I am booked for the entire weekend and need to sort this out asap. I can’t believe Denon release ONE public beta, then share all the rest to their “private testers” and don’t give users any further feedback. When they finally release their “tested & stable” version, it’s even worse than the beta!! Come on already! what the hell!!!
It doesn’t take that long to run a couple of sqlite commands… 30 mins max.
That being said, I’m not exactly happy they released this without an automated way to fix the corrupt databases, or at the very least identify which ones need fixing - maybe they underestimated how widespread this issue actually is outside of test environments.
I do also question your decision to update if you know you are booked for the weekend, surely it would be wiser to have waited for a quieter time and/or sat back for a bit and watched this forum to see what the potential issues are?
To be honest, this was definitely an oversight on my part. I shouldn’t have updated!!! I honestly thought that when Denon release their “stable / official” firmware it would be rock solid. If anything I thought it would be the same / better than the beta!! Sadly these problems just break our confidence in Denon.
Hi @JWiLL , I have Prime 4 and have been unable to deal with Database corrupt for several days. Database corrupt message began to appear after a sudden power failure. This error appears immediately every time the device is turned on, even when the media is not installed in it at all (neither SSD, nor USB) and it is called (Database of “Unknown” is corrupt) What is “Unknown”??? I do not understand. I tried many of the methods recommended on Denon forum, including SQLITE. But nothing helped. I sent logs and db files via “wetransfer” 21th of may as you recommended above but did not receive an answer yet. It’s still impossible to use the device…
Hello @Ypolor Welcome to the forum.
Did You tried to re-upload the software for You prime4? Maybe a fresh install would help to solve this issue…?
@NoiseRiser Yes, I did. When a power failure happened I had a 1.5 ver of engine os. Then I moved to 1.6 but nothing changed
Try once again, maybe also try different update options like multiple USB sticks, windows and mac computers? Something maybe will make it work.
@NoiseRiser Moved to 1.6.0 and back to 1.6.1. “Database of “Unknown” is corrupt” message appears even during the update
@Reese do You know maybe some fix for that?
I would try SQL tools as well, but do I read it correctly that there’s no storage attached and it still gives the error?
Exactly, that is a very strange problem. It looks like som kind of looped part of code getting executed on every startup…? Or something like this…