Could not load file or assembly 'file:///"path to dll"\mytests.dll' or one of its dependencies. The parameter is incorrect

I am facing this error while running the tests, the build works fine without ant issues. I can't seem to figure out why this is failing to load. I have looked over internet and tried all the solutions like clearing the .net temp files, updated the correct .net framework version that the project is intended to use and many other solutions on stack over flow but nothing worked. Can anyone help with this issue please ?

Console output:

Could not load file or assembly 'file:///"path to dll"\mytests.dll' or one of its dependencies. The parameter is incorrect. (Exception from HRESULT: 0x80070057 (E_INVALIDARG))