Lately, while trying to put in live a web application to my GoDaddy hosting account, I started to face some errors which were not present at my local development machine. I was receiving
Security Exception with a generic error stating no much information to lead me to the correct cause of the error. Then I remembered that GoDadddy has set its security level to
Medium Trust. After solving this problem, I thought it would be good to share this so here is my post regarding ASP.NET 4.5 Security Exception.
In order to simulate the environment, I added the following line to my web config file:
<trust level="Medium" />
Immediately, I started to receive the very same error locally. After trying few possible solutions, removed some libraries I was using, I was still receiving the very same error with slight changes in the stack trace, but still no help.
Description: The application attempted to perform an operation not allowed by the security policy. To grant this application the required permission please contact your system administrator or change the application’s trust level in the configuration file.
Exception Details: System.Security.SecurityException: Request for the permission of type ‘System.Security.Permissions.SecurityPermission, mscorlib, Version=18.104.22.168, Culture=neutral, PublicKeyToken=b77a5c561934e089’ failed.
Then I decided to test my solution in an environment with .NET 4.0 (not 4.5 as in my current development machine), and… voi·là, the application was working like a charm.
So, the first time, I really had problem with a library which was not able to perform under medium trust, however, what really mislead me was the Security Exception thrown by .NET 4.5 under medium trust. After a short research, I discovered that this is an issue to many developers and libraries such as DNN, and some others. I hope Microsoft will soon address this.
So you who use Visual Studio 2012, if you receive Security Exception under medium trust, please try to run your application in an environment with .NET 4.0 to test if the problem is with the .NET itself.
Hope this helps.