Your system is unable to reach the snap store

I tried to upgrade my windows ubuntu subystem to 18.10 using this instruction:https://linuxconfig.org/how-to-upgrade-ubuntu-to-18-10-cosmic-cuttlefish#h9-how-to-upgrade-ubuntu-the-debian-way

But within the upgrade I get this error:

 Your system is unable to reach the snap store, please make sure you're connected to the Internet and update any   ││ firewall or proxy settings as needed so that you can reach the snap store.                                        ││││ You can manually check for connectivity by running "snap info lxd"││││ Aborting will cause the upgrade to fail and will require it to be re-attempted once snapd is functional on the    ││ system.                                                                                                           ││││ Unable to reach the snap store

My firewall is disabled to I see no reason, why this would not work.

I also tried to run snap info lxd but

Interacting with snapd is not yet supported on Windows Subsystem for Linux.This command has been left available for documentation purposes only.

Here is the complete message in the command line, when trying to run the update:

The following additional packages will be installed:  lxdThe following packages will be upgraded:  lxd1 upgraded, 0 newly installed, 0 to remove and 227 not upgraded.180 not fully installed or removed.Need to get 0 B/11.1 kB of archives.After this operation, 20.5 MB disk space will be freed.Do you want to continue? [Y/n] yPreconfiguring packages ...(Reading database ... 61051 files and directories currently installed.)Preparing to unpack .../archives/lxd_1%3a0.4_all.deb ...invoke-rc.d: could not determine current runlevelStopping Container hypervisor based on LXC: (not running).=> Installing the LXD snap==> Checking connectivity with the snap store===> Unable to contact the store===> Aborting at user requestdpkg: error processing archive /var/cache/apt/archives/lxd_1%3a0.4_all.deb (--unpack): new lxd package pre-installation script subprocess returned error exit status 1invoke-rc.d: could not determine current runlevelErrors were encountered while processing: /var/cache/apt/archives/lxd_1%3a0.4_all.debE: Sub-process /usr/bin/dpkg returned an error code (1)

Any idea, how I can fix that? The subsystem has internet connection, so I'm not sure, why it can't connect to the snap store