E117: Unknown function: netrw#Explore

After migrating my WSL from Ubuntu 18.04 to Ubuntu 20.04 I started getting the error:

E117: Unknown function: netrw#Explore

When I hit :E to launch the file Explorer on Gvim.

I have disabled all the plugins but I still get the error message.

I have no idea where to start debugging.

version 8.1.3741

$gvim --version

VIM - Vi IMproved 8.1 (2018 May 18, compiled Feb 01 2022 09:16:32)
Included patches: 1-2269, 3612, 3625, 3669, 3741
Modified by team+vim@tracker.debian.org
Compiled by team+vim@tracker.debian.org
Huge version with GTK3 GUI.  Features included (+) or not (-):
+acl               -farsi             -mouse_sysmouse    -tag_any_white
+arabic            +file_in_path      +mouse_urxvt       +tcl
+autocmd           +find_in_path      +mouse_xterm       +termguicolors
+autochdir         +float             +multi_byte        +terminal
-autoservername    +folding           +multi_lang        +terminfo
+balloon_eval      -footer            -mzscheme          +termresponse
+balloon_eval_term +fork()            +netbeans_intg     +textobjects
+browse            +gettext           +num64             +textprop
++builtin_terms    -hangul_input      +packages          +timers
+byte_offset       +iconv             +path_extra        +title
+channel           +insert_expand     +perl              +toolbar
+cindent           +job               +persistent_undo   +user_commands
+clientserver      +jumplist          +postscript        +vartabs
+clipboard         +keymap            +printer           +vertsplit
+cmdline_compl     +lambda            +profile           +virtualedit
+cmdline_hist      +langmap           -python            +visual
+cmdline_info      +libcall           +python3           +visualextra
+comments          +linebreak         +quickfix          +viminfo
+conceal           +lispindent        +reltime           +vreplace
+cryptv            +listcmds          +rightleft         +wildignore
+cscope            +localmap          -ruby              +wildmenu
+cursorbind        +lua               +scrollbind        +windows
+cursorshape       +menu              +signs             +writebackup
+dialog_con_gui    +mksession         +smartindent       +X11
+diff              +modify_fname      +sound             -xfontset
+digraphs          +mouse             +spell             +xim
+dnd               +mouseshape        +startuptime       +xpm
-ebcdic            +mouse_dec         +statusline        +xsmp_interact
+emacs_tags        +mouse_gpm         -sun_workshop      +xterm_clipboard
+eval              -mouse_jsbterm     +syntax            -xterm_save
+ex_extra          +mouse_netterm     +tag_binary
+extra_search      +mouse_sgr         -tag_old_static
   system vimrc file: "$VIM/vimrc"
     user vimrc file: "$HOME/.vimrc"
 2nd user vimrc file: "~/.vim/vimrc"
      user exrc file: "$HOME/.exrc"
  system gvimrc file: "$VIM/gvimrc"
    user gvimrc file: "$HOME/.gvimrc"
2nd user gvimrc file: "~/.vim/gvimrc"
       defaults file: "$VIMRUNTIME/defaults.vim"
    system menu file: "$VIMRUNTIME/menu.vim"
  fall-back for $VIM: "/usr/share/vim"
Compilation: gcc -c -I. -Iproto -DHAVE_CONFIG_H -DFEAT_GUI_GTK  -pthread -I/usr/include/gtk-3.0 -I/usr/include/at-spi2-atk/2.0 -I/usr/include/at-spi-2.0 -I/usr/include/dbus-1.0 -I/usr/lib/x86_64-linux-gnu/dbus-1.0/include -I/usr/include/gtk-3.0 -I/usr/include/gio-unix-2.0 -I/usr/include/cairo -I/usr/include/pango-1.0 -I/usr/include/fribidi -I/usr/include/harfbuzz -I/usr/include/atk-1.0 -I/usr/include/cairo -I/usr/include/pixman-1 -I/usr/include/uuid -I/usr/include/freetype2 -I/usr/include/libpng16 -I/usr/include/gdk-pixbuf-2.0 -I/usr/include/libmount -I/usr/include/blkid -I/usr/include/glib-2.0 -I/usr/lib/x86_64-linux-gnu/glib-2.0/include -Wdate-time  -g -O2 -fdebug-prefix-map=/build/vim-9EpYYi/vim-8.1.2269=. -fstack-protector-strong -Wformat -Werror=format-security -D_REENTRANT -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=1
Linking: gcc   -Wl,-E  -Wl,-Bsymbolic-functions -Wl,-z,relro -Wl,-z,now -Wl,--as-needed -o vim   -lgtk-3 -lgdk-3 -lpangocairo-1.0 -lpango-1.0 -lharfbuzz -latk-1.0 -lcairo-gobject -lcairo -lgdk_pixbuf-2.0 -lgio-2.0 -lgobject-2.0 -lglib-2.0 -lSM -lICE -lXpm -lXt -lX11 -lXdmcp -lSM -lICE  -lm -ltinfo -lnsl  -lselinux  -lcanberra -lacl -lattr -lgpm -ldl  -L/usr/lib -llua5.2 -Wl,-E  -fstack-protector-strong -L/usr/local/lib  -L/usr/lib/x86_64-linux-gnu/perl/5.30/CORE -lperl -ldl -lm -lpthread -lcrypt  -L/usr/lib/python3.8/config-3.8-x86_64-linux-gnu -lpython3.8 -lcrypt -lpthread -ldl -lutil -lm -lm -L/usr/lib/x86_64-linux-gnu -ltcl8.6 -ldl -lz -lpthread -lm

Here is the content of my .vimrc file

=======================================================================

set directory=%TMP%,~/.tmp
set backupdir=%TMP%,~/.tmp

 set rtp+=~/.vim/bundle/Vundle.vim
 call vundle#begin()
 "Let Vundle manage Vundle
 "required:  all the plugins should be located in ~/.vim/bundle
 Plugin 'Vundle/Vundle.vim'
 Plugin 'vim-scripts/Align.git'
 Plugin 'vim-scripts/The-NERD-tree.git'
 Plugin 'vim-scripts/surround.git'
 "Plugin 'vim-scripts/snipMate.git'
 Plugin 'vim-scripts/taglist.vim.git'
 Plugin 'vim-scripts/pyte.git'
 Plugin 'vim-scripts/asciidoc.vim.git'
 Plugin 'vim-scripts/The-NERD-Commenter.git'
 Plugin 'vim-scripts/VHDL-indent-93-syntax.git'
 Plugin 'vim-scripts/tagbar'
 Plugin 'vim-scripts/FastFold'
 Plugin 'vim-scripts/verilog_systemverilog.vim.git'
 "Plugin 'vim-scripts/fugitive.vim.git'
 Plugin 'vim-scripts/python.vim.git'
 Plugin 'vim-scripts/ctrlp.vim.git'
 Plugin 'vim-scripts/Solarized'
 " ==>Plugin 'vim-scripts/Distinguished.git'
 Plugin 'vim-scripts/jellybeans.vim.git'
 Plugin 'vim-scripts/VimOutliner.git'
 Plugin 'vim-scripts/VimOrganizer.git'
 Plugin 'vim-scripts/Auto-Pairs.git'
 Plugin 'vim-scripts/calendar.vim--Matsumoto.git'
 Plugin 'vim-scripts/L9'
 Plugin 'vim-scripts/fuzzyfinder'
 Plugin 'vim-scripts/vim-snippets'
 Plugin 'vim-scripts/vim-obsession'
 Plugin 'vim-scripts/ultisnips'
 Plugin 'vim-scripts/obsession'
 "Plugin 'vim-scripts/Vimliberty'
 Plugin 'bling/vim-airline'
 call vundle