XML Schema throwing permission failed warning

I have an xml document and schema and when I open the xml document in visual studio I get a bunch of warnings like:

Request for the permission of type 'System.Security.Permissions.FileIOPermission, mscorlib, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561开发者_运维技巧934e089' failed.

Does anyone know what might be the cause of these warnings? It is making it difficult to validate the xml document. Also when I hover over the squiggly line under the schemaLocation attribute value, the tool tip gives the error "The schema referenced from this location in your document contains errors"

Thanks in advance!

Turns out this is a Visual Studio specific problem. I loaded the xml document in Altova's XMLSpy and it worked just fine.