Cannot import torch Error loading ..\caffe2_nvrtc.dll"

I am on a Windows 10 64 bit system. Pytorch for cuda has been working successfully for some time. Today I tried to upgrade to the latest version of Pytorch (1.13) using

conda install pytorch torchvision torchaudio pytorch-cuda=11.7 -c pytorch -c nvidia

Now I cannot import torch. I get the error:

OSError: [WinError 126] The specified module could not be found. Error loading “C:\Users\alan\anaconda3\lib\site-packages\torch\lib\caffe2_nvrtc.dll” or one of its dependencies.

I have tried both in a Jupyter notebook and in the Spyder IDE.

I have tried completely removing Anaconda and reinstalling afresh and then reinstalling Pytorch with no success. I do not believe I have any other versions of python installed.

The offending dll (caffe2_nvrtc.dll) does seem to be in the file location specified.

I have found various similar problems reported but they all date back to 2020 or earlier and none of them seemed to have a satisfactory solution.

Can anyone point me in the correct direction