Run tests for methods that are not static

I have an algorithm written using OOP, therefore I have different Classes and methods for each of them.

I want to create an Unit Test for a method that is not static.

When I run the test for that specific method I got an error that the unit test cannot be executed for a method that is not static.

Can somebody help me?

[Steven Lord]

I know for a fact that it is possible to unit test class methods (both Static and non-Static.)

Can you show a simple example of the class you're trying to test and one of your test methods that attempts to test it? Including the full and exact text of the error message you receive will also be useful, as the exact wording may suggest the cause of the error.