I took my cow's four day old calf off her to make her let down, I also have given her snacks to help her let down and bunted her. I have also tried getting the calf to suck so she lets down,, but she won't. Does anyone know how to make her let down?
It sounds as if for some reason, or another, your cow is very stressed out. This is causing a release of adrenalin in her system that is preventing her from letting down.
You need to identify the cause of this. If could be that she was frightened by something of late, or that she has been moved to unfamiliar surroundings ...
You really have to find out what is causing her fear. Once you do this, you will have her milking again.
However, this may take weeks. First of all you have to identify the problem, but then after that you may have to spend a lot of time reassuring her that she has nothing to fear anymore before her behavior changes and she starts allowing you to milk her again.