Today I was creating a new DotNetNuke portal with version 3.3.5. When I accessed a module that uses special control inherited from the DNNTreeView control fromdotnetnuke.webcontrols.dll, I encountered this error:

Request for the permission of type System.Security.Permissions.SecurityPermission, mscorlib, Version=1.0.5000.0, Culture=neutral, PublicKeyToken=b77a5c561934e089 failed

This error does not happen on any of the other sites using the custom module in question. I did some google searching and learned that I needed to change the trust level of the dnn application from Medium to Full in the web.config file. After doing this, I received this error:

Assembly freetextbox.dll security permission grant set is incompatible between appdomains.

I wasted 2 hours toggling settings, viewing code security settings, blah blah blah. Frustration set in and I rebooted my computer. Problem solved. Seriously.

On a separate issue, I found that DotNetNuke version 3.3.7 was released a few months ago. I installed the upgrade and managed to fix an error in the 3.3.5 Module Uploader. That was bombing with the vague message "External component has thrown an exception". It occured the first time after I noticed that my portal went through a second installation routine after the application started the second time. Since then, I could do pretty much everything with the portal except upload new modules. Glad that one's fixed!