CUDA 9.1 installation error: does not have a version.txt file! Ensure you are installing to an existing toolkit directory

You might be trying to install the "patch" instead of the main installer.

---

Is your file about 70 MB size instead of the more expected 1.7 GB size? If yes, then you are probably installing the "patch" first before the main installer.

I also tried installing the "patch" first and got an error and then I was confused. Then I realized I had the wrong filename and did an ls -alrth and got the filename for the larger 1.7 GB installer and tried that and now it is installing without the error message.

The files I downloaded were not clearly labeled to indicate what file was the installer and what was the main installer (the filenames are all cuda_${version}.run).