FreeTextBox can't load dependency but it works

I am having a bizarre problem. I installed FreeTextBox for my ASP.NET project (WebForms) and I set it all up and its working perfectly, it does what needs to be done. In the solution though, after a few compiles, I get the following error:

Error   1   'Could not load file or assembly 'FreeTextBox, Version=3.3.1.12354,
Culture=neutral, PublicKeyToken=5962a4e684a48b87' or one of its dependencies. 
Operation is not supported. (Exception from HRESULT: 0x80131515)'   

The error is in the licenses.licx file. If I delete that line the program compiles without issue and I can use it, but after several compilations the problem pops back up and I need to delete it. I verified around the internet and found no defining answer to be honest.

Did you download freetextbox.dll from the web? If yes, then right click and choose 'Unblock'. It might have been blocked for some reasons.