Referenced assembly cannot be found. Custom .DLL
I am trying to use a custom .DLL. I have written it in C#, have added it to the component library under namespace testdll. The namespace in the class is also testdll and the class is called testdll. When I try and use it in an expression, I keep getting the error referenced assembly testdll.dll cannot be found.
When I manually add the .dll into the Bin folder of the project (WebApplication\bin) I still get the error, but the .dll is called properly and returns the proper results.
Why is this happening? Any help is much appreciated!