Ubuntu app on WSL doesn't recognise Windows symlinks

In this question, I already asked a first question on the Ubuntu app on a Windows machine, this was about a Ubuntu app I installed on my computer at work.

Now I've tried to do the same with WSL on my computer at home, but it seems not to work.

First some general information:

First line of help result:

GNU bash, version 4.4.19(1)-release (x86_64-pc-linux-gnu)

uname -a result:

Linux DESKTOP-D0GIHSU 4.4.0-17763-Microsoft #864-Microsoft Thu Nov 07 15:22:00 PST 2019 x86_64 x86_64 x86_64 GNU/Linux

I've again used Windows mklink C C:\ command for creating a Windows symlink in the root directory of my Ubuntu app, but this time it seems not to work:

Windows dir command result excerpt:

19/12/2019  14:35    <SYMLINKD>     C [C:\]

(I followed the link and while doing a dir, the results of dir C:\ are shown, so it works)

Ubuntu app ls -ltra | grep C result:

ls: cannot access 'C': Input/output error
d?????????  ? ?    ?         ?            ? C

Anybody has an idea what's going wrong?
Thanks in advance