Thank you for that @rolfbjarne, it is appreciated. 🙏 I hope you'll understand my surprise, however, that the repository dedicated to iOS development doesn't seem to know the answer to this question, which to me seems like a basic one. I guess I am quickly learning that the simulator is not used very much at all with typical development. In any case, I do appreciate you pointing me in the right direction. 👍

Looking a bit more at this, it's kind of related to using the free apple developer account, because creating provisioning profiles is not allowed there it seems.

As a workaround, try adding this to your csproj:

<Target Name="NoProvisioningProfiles" BeforeTargets="_DetectSigningIdentity">
  <PropertyGroup Condition="$(RuntimeIdentifier.Contains('simulator'))">
    <CodesignRequireProvisioningProfile>false</CodesignRequireProvisioningProfile>
  </PropertyGroup>
</Target>

The good news is that this will be fixed in .NET 10 (it was very recently fixed).

Hi @rolfbjarne thank you very much for the suggestion. That did seem to resolve that error that I had, but now I have a new one. 😁

Here's my Entitlements.plist

<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
<plist version="1.0">
	<dict>
		<key>keychain-access-groups</key> 
		<array> 
			<string>$(AppIdentifierPrefix)<ApplicationId></string> 
		</array>
	</dict>
</plist>

Where <ApplicationId> is the <ApplicationId> in csproj.

A warning is generated:

Cannot expand $(AppIdentifierPrefix) in Entitlements.plist without a provisioning profile for key 'keychain-access-groups' with value '$(AppIdentifierPrefix)<ApplicationId>'.

And an error:

MessagingRemoteException: A problem occurred while deserializing an error message for topic build4216842168micha/error/xvs/build/18.5.9199/execute-task/Application.Mobile.Application.Maui/052dab4002fAOTCompile
JsonSerializationException: Error resolving type specified in JSON 'System.Collections.Generic.List`1[[Xamarin.Messaging.Exceptions.ExceptionSerializableProperty, Xamarin.MacDev.Tasks]], System.Private.CoreLib'. Path 'InnerExceptionInformation.SerializableProperties.$type'.
JsonSerializationException: Could not load assembly 'System.Private.CoreLib'.

Thank you for any further assistance you can provide. 🙏

The "$(AppIdentifierPrefix)" part comes from a provisioning profile, so if you don't have one, our build notifies you about it. One way to silence the warning would be to remove the "$(AppIdentifierPrefix)" part, so that the line is "". Or alternatively you can just ignore the warning if the app works as expected.

The error sounds like a bug, I would suggest filing an issue about it.