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Xamarin.Forms iOS crash on XAML pages with custom controls

I am working on a Xamarin.Forms project, for which I recently upgraded the shared projects from PCL to .NETStandard.
At that point, I encountered build issues coming from several of my UI XAML files, with the error being:
Failed to resolve assembly: ‘MyAssembly, Version 0.0.0.0,
Culture=neutral, PublicKeyToken=null’
The problem files were found to be those that referenced custom XAML controls. After finding several people with similar issues online, I eventually found that I could get past this issue by setting the XamlCompilationOptions for those pages from Compile to Skip. The project now builds for iOS and Android.
The Android version works normally, however for the iOS version crashes when one of those pages tries to load, due to the presence of the custom control, with an error such as:
Xamarin.Forms.Xaml.XamlParseException … Type shared.SharedControl not
found in xlmns clr-namespace: …
Has anyone encountered this issue, and if so, did you solve it? Is it a code issue or a Xamarin / Visual Studio Mac bug?
Ideally I would like to not have to set the XamlCompilationOptions for those pages to Skip, but either way I don't see why it should affect iOS but not Android.

Firstly, XamlCompilationOptions.Compile means Compile the XAML for the class or project when the application is built.While XamlCompilationOptions.Skip do the same thing when the application is run on the device.
In addition ,I suggest that you can do following steps:
Delete and Re-generate all share files
Remove ;assembly:xxx from App.xaml
Clean and build again.
Here is a similar thread for you referring toXamarin.Forms.Xaml.XamlParseException has been thrown
PS:There is a link about how to Upgrade PCL to .NET Standard Class Library

You need to load that assembly before using it. On Xaml it does not load, just try to reach, and crashes if its not loaded. Before using it you need to load assembly by calling a method, or creating an object belong MyAssembly.
There should be a Init method for the assembly to init things. you should call it.

Trying to get the package current version causes errors APPX1706 and APPX1704

I have some troubles with Windows.ApplicationModel.Package class.
When I try to add the reference to Windows.ApplicationModel or when I'm getting the current package, 17000+ errors appears.
How I try to get the current package :
var myPackage = Windows.ApplicationModel.Package.Current;
The kind of error I get :
error APPX1704: The file .winmd 'Windows.Foundation.UniversalApiContract.winmd' contains type 'Windows.Graphics.Effects.IGraphicsEffect'. The use of spacename Windows is reserved.
Or
error APPX1706: The .winmd file 'Windows.Foundation.UniversalApiContract.winmd' contains type 'Windows.Graphics.Effects.IGraphicsEffect' outside its root namespace 'Windows.Foundation.UniversalApiContract'. Make sure that all public types appear under a common root namespace
that matches the output file name.
Is there a solution to this problem or a better way to get the current version ?

For the first problem I am a bit uncertain, but it is always good idea to reboot (ide, os, etc.), if this is not helping maybe reinstall the SDK, IDE. I know this is not complete answer, it is just from experience.
The second error is saying that your namespaces are not consistent. It means that instead of having Example.Logic, Example.Domain, Example.Utils - you have something like Example.Logic, Test.Domain, Utils (inconsistency of namespaces).

I found the source of the issue, it was due to the structure of the solution.
Just like in a Xamarin application, we have a "Core" project that contains the application logic.
We tried to use some Windows app specific namespaces in these shared classes, instead of creating an interface in the Core project and implementing it in the UWP project.
Removing the line with the reference to the Windows.ApplicationModel.Package class from the core project and move it to the UWP project resolved the issue.
Sorry for the lack of information on the original post.

DLLNotFoundException under Unity whilst using FUBI

I'm currently working on my Bachelor-Thesis, which revolves around extending the functions of a Kinectv2 in an Unity-environment.
However, I have little-to-no experience with Unity and C# and whilst setting up the FUBI library (which will be a core of my Thesis), I ran into this problem right away:
Upon starting the Unity project (provided by FUBI), I get a
DLLNotFoundException: FUBI.64.dll
followed by a plethora of errors from failing calls on said library.
The confusing part, to me: Back in university we decided to use FUBI, because we managed to install it, outofthebox, with zero issues within a few minutes. But now, at my home tower (Windows 10 and Unity 5.3.5, just like the machine at the university), this error persists.
The Unity project and all required DLL's are provided in a single download from the FUBI-website itself, which implies that the error shouldn't lay in the project, the provided DLL's or any weird dependancys.
The only thing one has to do (according to FUBI's readme) besides unpacking the zip containing the project is:
IMPORTANT: After installing the Kinect SDK, please execute the "CopyFaceTrackRedist.bat" located in the FubiUnity base folder or manually copy the "Kinect20.Face.dll" and "NuiDatabase" from the Kinect Developer Toolkit to that folder.
Which I've done via the bat, executed flawlessy and had both mentioned files/folders copied into the project directory.
Whilst trying to fix this, I started manually moving the Fubi64.dll to various locations within the Unity project, but the only result was Unity mentioning it found multiple instances of said dll, would only use one, and then throw the exception nontheless.
I've started to think it may be a dependency thing, but downloading and using the dependencywalker gave me little to no useable results.
(I mean, it's showing some errors, but afaik those are related to DW not being updated and unable to work with some forward-dependency-shenanigans or something, according to some other thread on stackflow I've read.)
Any help, or even pointers at what to try next, would be appreciated.

Spending days chasing after the issue, I finally found one entry in dependencywalker that made sense and after manually installing MPFLAT.dll into windows\system32, Unity was able to load the dll just fine. I would assume it's some dll related to mediaviewer or associated tools, since those don't come natively with Win10, I didn't specifically install any yet and it is well possible the other mentioned tower had something installed that brought the DLL along.

Frame.Navigate to a Page-derived class in a different assembly

I'd like to keep my Windows Phone 8 Blank App template based view in a different assembly than the assembly containing the application manifest and App.xaml.
I keep receiving a cryptic exception which doesn't help at all in figuring out how to fix it:
Create a new project from the template Visual C# > Store Apps > Windows Phone Apps > Blank App (Windows Phone).
Build and deploy, works great. The properties of the MainPage.xaml state the Build Action is Page, which is correct.
Create a new project based on the Class Library (Windows Phone) template from the same category within the solution containing the original project, call it MyApp.Views.
Move the MainView.xaml file to the newly created project using Cut and Paste commands.
Add a reference to MyApp.Views to the original project.
Build, deploy, see the app start and fail to locate the view only to propagate this exception back to the developer's box: ComException: Error HRESULT E_FAIL has been returned from a call to a COM component. This doesn't say absolutely anything at all useful and the top stack frame is Windows.UI.Xaml.Controls.Frame.Navigate(Type sourcePageType, Object parameter) following the first one, which is TheOriginalProject.App.OnLaunched(LaunchActivatedEventArgs e).
The solution is not to use NavigationService with pack URI since it seems to be absent in Windows Phone 8, or at very least the assembly containing it is not referenced by default in the Blank App template. In any event, I'd vastly prefer strongly typed view names over pack URIs.
I imagine someone must've run into this issue already, what's the catch? Is there an API or a tool that will give me an insight on what the latest E_FAIL coming from COM is?
Edit: When using Window.Current.Content = new MainPage() as the only content of OnLaunched, the XAML parser exception pops up. It is unable to populate an exception message, but definitely gives a better hint to what's going on. Still no solution, though, the problem only moved to the this.InitializeComponent() in the MainPage constructor.
What I see now is Windows.UI.Xaml.Markup.XamlParseException with WinRT information of Parser internal error: Object writer '%0' and Additional information unable to load. x:Class attribute is present at the position 128 hinted on by the exception dialog window and this thread seems relevant, but I can't work out how.
Please note that I'll also find values in people confirming not receiving the error I do. If you've tried the steps to reproduce and failed to reproduce the problem, please write a comment so I can pin down what it is that causes the error I'm struggling with.

Alternative solution to externalizing views to a separate project while avoiding this problem is to use a Shared project project type, put the views there and reference it from the main project.
This does not produce a separate assembly for the views, instead the files are just grouped within their custom project, but behave as if they were part of the main project during compilation. The error goes away because from the compiler point of this, there's no difference between a file in a shared project and a file directly in the main project. During runtime, the type of the view doesn't need to be resolved from a different assembly, it's right there in the same assembly.

Strange exception suddenly appears when trying to install a setup project, need help big time

Using Visual Studio 2010 to build a setup project that installs a Windows Forms application .Net 4.0 C#. It has worked fine for ages but now when I'm trying to install the finished setup file, I'm getting this error message:
Error 1001. Unable to get installed types in the "Path" assembly. -->
Unable to load one or more of the requested types. Retrieve the
LoaderExceptions property for more information.
I have been searching for answers for over 4 hours now without finding anything. This problem just came without me doing anything. Last time I build the install file was like 2 weeks ago and there was NO problem at all. I haven't deleted any reference or any code that have anything to do with the setup project.
How could this problem appear from nothing and more important, how do I fix it?

Based on the error message in your second comment, it appears that your SysDir.exe assembly has been added as a Custom Action with the InstallerClass property set to true, but either no installer classes could be found in the exe or the exe could not be loaded due to missing dependencies.
You can see the list of Custom Actions by right-clicking on the installer project, selecting View and then Custom Actions.
If your exe does not can an installer class, then you can remove it from the list of custom actions.
If it does contain an installer class, then the issue is going to be missing dependencies. If fuslogvw doesn't work for you (it has always helped resolve this kind of issue for us), you can carefully review the list of references in the exe's project and compare them to what is listed in the installer project.
The other trick that we use is to examine the install directory while the error message is displayed on the screen. We can often see that DLLs are missing by doing this, usually because the path was entered incorrectly in the DLL entry within the installer project or because a condition was set incorrectly.

Have the same error today. For me it was the project type of the class library.
I noticed that the pucture on the guide I was following had selected Class Library (.NET Framework) instead of just Class Library.
Creating the correct project type fixed the error.
https://nhvu1988.com/posts/how-to-create-msi-installer-using-vs-installer/