Just a quicky post…
This is only ONE reason you may have gotten this error and I wanted to share this. If this does not solve your issue engage the forums or get assisted support from your developer dashboard.
I had a customer that was getting this error when uploading his xap file: error: 2004: Something’s happened, and we’re not quite sure what. We haven’t lost any of your app’s info, so try resubmitting again.
Cause: .NET Reactor version 4.8 bug
Resolution: Remove the "Inject Invalid Metadata” setting under Anti-ILDASM, or upgrade to version 4.9 of .NET Reactor (Store app only, phone not fixed)
Let me know if this helped! If it did not hit the MSDM forums or assisted support, both available from your Developer dashboard. I will not attempt any further troubleshooting from this blog, but if you DO find a resolution that is different from this… Zap a comment and I will add it to the Blog!