I had the same problem, so don't worry. It may seem troublesome because uninstalling and reinstalling Spyder doesn't work and neither does uninstalling and reinstalling Anaconda altogether (at least it didn't work for me). I've spoken with prof. Mancini of this same issue and he suggested to delete anaconda's and spyder's files from the pc. To do this go on C:/Users/name_of_your_user/ and uninstall all files Anaconda related: .conda (and literally any other folder). Then, make the secret directories be visible, from name_of_your_user go on appdata and uninstall the folder called Spyder. After this reinstall Anaconda. Anaconda's environment has been fixed. Reinstall the libraries.
Now you can try installing Spyder 5, based on a response on stackoverflow:
The problem is with the Anaconda channel.
I uninstalled Spyder and then install with the line:
conda install spyder
and Spyder 5.0.0 was successfully installed.
Anaconda's Spyder page (
https://anaconda.org/anaconda/spyder) gave the command as:
conda install -c anaconda spyder
which led to the installation of Spyder 4.0.1, instead of 5.0.0 which was what it was supposed to install as documented on the page itself.
Instead of cancelling everything as I suggested above, you can try (but I can't tell you for sure because I never used these):
conda update anaconda
and then
conda install spyder=5
Let me know if any of these work