Okay I learned from this thread that it's probably related to permissions: https://our.umbraco.com/forum/umbraco-7/using-umbraco-7/71896-object-reference-not-set-to-an-instance-of-an-object

Make sure that the app pool identity has access to create and modify the "access.config" file in the "App_Data" folder.

Question is: I don't have that file and how do I change the permissions if I don't have a local IIS running? I'm working directly from the host UnoEuro.

Here's a quick video of the error if that helps: https://www.youtube.com/watch?v=35RC3xQYGdM&feature=youtu.be

// Mike

An Object is an instance of a Class , it is stored some where in memory. A reference is what is used to describe the pointer to the memory location where the Object resides. The message "object reference not set to an instance of an object" means that you are referring to an object the does not exist or was deleted or cleaned up. It's usually better to avoid a NullReferenceException than to handle it after it occurs. To prevent the error, objects that could be null should be tested for null before being used.

if (mClass != null)
{
  // Go ahead and use mClass
  mClass.property = ...
}
else
{
  // Attempting to use mClass here will result in NullReferenceException
}

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