I installed TensorFlow on my Windows Python 3.5 Anaconda environment The validation was successful (with a warning)
(tensorflow) C:\\>python
The reason Python 3.5 environment is unable to import Tensorflow is that Anaconda does not store the tensorflow package in the same environment.
One solution is to create a new separate environment in Anaconda dedicated to TensorFlow with its own Spyder
conda create -n newenvt anaconda python=3.5
activate newenvt
and then install tensorflow into newenvt
I found this primer helpful