Can't deploy even blank app to Windows IoT on RPi2

I'm using Windows 10 (10.0.14393) with enabled developer mode. I have latest update of Visual Studio 2015.

What I'm doing (note this is blank project with Windows IoT Extension for the UWP ver. 10.0.14393.0):

1. Start remote debugger at RPi and setup VS at address (without Authentication mode)
2. Start debugging (remote device, ARM)
3. I get this error message:

The project "Test" needs to be deployed before it can be started.

Verify the project is selected to be deployed in the Solution Configuration Manager, or deploy it explicitly by clicking one of the Deploy commands in the Build menu.

If I try to verify project I can't find it in there - I see only debug, release, new or edit.

4. I deploy (Build -> Deploy Solution) and I get this error message:

Error DEP0700: Registration of the app failed. Failed to register through new deployment pipeline. (0x80004005)

Error DEP8000: Unexpected deployment failure : RemoteCommandException : Windows cannot register package c820041a-da82-4e55-b136-83591b83e844 because it is in development mode and the package is already installed. Increment the version number of the package to be registered, or remove the old package for every user on the system before registering this package. 0x80073cfb

I've tried to also deploy IoTCoreDefaultApp from github and I get same errors.

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About Raspberry: version 2 model B, fresh instalation of latest Windows IoT Core with latest update.

It looks like I'll go back to 10586, I want this version because it supports remote client.

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What I've tried and failed to fix this:

1. Disable developer mode, deploy, enable developer mode
2. Delete package family folder at C:\Users\\AppData\Local\Packages\
3. Reboots RPi and PC

I'm still not sure what casued this problem. Since I need to move on in my project I went back to Windows IoT Core version 10586 and disabled auto-update by this guide. Now it works fine. After October I'll try to get back to it and try to find what was wrong.