Repository: nvm
Issue: cannot use nvm to downgrade node version
Labels: OS: windows,needs followup,installing nvm

#1461 ## Operating system and version:
Windows 10 Pro Version	10.0.18363 Build 18363

#### `nvm debug` output:
<details>
<!-- do not delete the following blank line -->

```sh
nvm --version: v0.35.3
$TERM_PROGRAM: Hyper   
$SHELL: /usr/bin/bash  
$SHLVL: 1
${HOME}: /c/Users/diama
${NVM_DIR}: '${HOME}/.nvm'
${PATH}: ${HOME}/bin:/mingw64/bin:/usr/local/bin:/usr/bin:/bin:/cmd:/c/ProgramData/Oracle/Java/javapath:/c/Program Files (x86)/Intel/iCLS Client:/c/Program Files/Intel/iCLS Client:/c/WINDOWS/system32:/c/WINDOWS:/c/WINDOWS/System32/Wbem:/c/WINDOWS/System32/WindowsPowerShell/v1.0:/c/Program Files (x86)/Intel/Intel(R) Management Engine Components/DAL:/c/Program Files/Intel/Intel(R) Management Engine Components/DAL:/c/Program Files (x86)/Intel/Intel(R) Management Engine Components/IPT:/c/Program Files/Intel/Intel(R) Management Engine Components/IPT:/c/WINDOWS/System32/OpenSSH:/c/Program Files/Intel/WiFi/bin:/c/Program Files/Common Files/Intel/WirelessCommon:/cmd:/c/Program Files/Java/jdk1.8.0_101/bin:/c/Program Files/nodejs:${HOME}/AppData/Local/Microsoft/WindowsApps:${HOME}/AppData/Local/atom/bin:${HOME}/AppData/Local/Microsoft/WindowsApps:${HOME}/AppData/Local/hyper/app-3.0.2/resources/bin:${HOME}/AppData/Local/Programs/Microsoft VS Code/bin:${HOME}/AppData/Roaming/npm:/usr/bin/vendor_perl:/usr/bin/core_perl
$PREFIX: ''
${NPM_CONFIG_PREFIX}: ''
$NVM_NODEJS_ORG_MIRROR: ''
$NVM_IOJS_ORG_MIRROR: ''  
shell version: 'GNU bash, version 4.4.23(1)-release (x86_64-pc-msys)'
uname -a: 'MINGW64_NT-10.0 2.11.2(0.329/5/3) 2018-11-10 14:38 x86_64 Msys'
curl: /mingw64/bin/curl, curl 7.64.0 (x86_64-w64-mingw32) libcurl/7.64.0 OpenSSL/1.1.1a (Schannel) zlib/1.2.11 libidn2/2.1.1 nghttp2/1.36.0
wget: not found
git: /mingw64/bin/git, git version 2.21.0.windows.1
grep: /usr/bin/grep, grep (GNU grep) 3.1
awk: /usr/bin/awk, GNU Awk 4.2.1, API: 2.0 (GNU MPFR 4.0.2, GNU MP 6.1.2)
sed: /usr/bin/sed, sed (GNU sed) 4.7
cut: /usr/bin/cut, cut (GNU coreutils) 8.30
basename: /usr/bin/basename, basename (GNU coreutils) 8.30
rm: /usr/bin/rm, rm (GNU coreutils) 8.30
mkdir: /usr/bin/mkdir, mkdir (GNU coreutils) 8.30
xargs: /usr/bin/xargs, xargs (GNU findutils) 4.6.0
nvm current: system
which node: /c/Program Files/nodejs/node
which iojs: which: no iojs in (${HOME}/bin:/mingw64/bin:/usr/local/bin:/usr/bin:/bin:/cmd:/c/ProgramData/Oracle/Java/javapath:/c/Program Files (x86)/Intel/iCLS Client:/c/Program Files/Intel/iCLS Client:/c/WINDOWS/system32:/c/WINDOWS:/c/WINDOWS/System32/Wbem:/c/WINDOWS/System32/WindowsPowerShell/v1.0:/c/Program Files (x86)/Intel/Intel(R) Management Engine Components/DAL:/c/Program Files/Intel/Intel(R) Management Engine Components/DAL:/c/Program Files (x86)/Intel/Intel(R) Management Engine Components/IPT:/c/Program Files/Intel/Intel(R) Management Engine Components/IPT:/c/WINDOWS/System32/OpenSSH:/c/Program Files/Intel/WiFi/bin:/c/Program Files/Common Files/Intel/WirelessCommon:/cmd:/c/Program Files/Java/jdk1.8.0_101/bin:/c/Program Files/nodejs:${HOME}/AppData/Local/Microsoft/WindowsApps:${HOME}/AppData/Local/atom/bin:${HOME}/AppData/Local/Microsoft/WindowsApps:${HOME}/AppData/Local/hyper/app-3.0.2/resources/bin:${HOME}/AppData/Local/Programs/Microsoft VS Code/bin:${HOME}/AppData/Roaming/npm:/usr/bin/vendor_perl:/usr/bin/core_perl)
which npm: /c/Program Files/nodejs/npm
npm config get prefix: C:\Users\diama\AppData\Roaming\npm
npm root -g: C:\Users\diama\AppData\Roaming\npm\node_modules
```
</details>

#### `nvm ls` output:
<details>
<!-- do not delete the following blank line -->

```sh
->       system
iojs -> N/A (default)
node -> stable (-> N/A) (default)
unstable -> N/A (default)
lts/* -> lts/erbium (-> N/A)
lts/argon -> v4.9.1 (-> N/A)
lts/boron -> v6.17.1 (-> N/A)
lts/carbon -> v8.17.0 (-> N/A)
lts/dubnium -> v10.20.1 (-> N/A)
lts/erbium -> v12.16.3 (-> N/A)
```
</details>

#### How did you install `nvm`?
<!-- (e.g. install script in readme, Homebrew) -->
curl -o- https://raw.githubusercontent.com/nvm-sh/nvm/v0.35.3/install.sh | bash

#### What steps did you perform?
nvm install 12.6.2

#### What happened?
Can not determine how many core(s) are available, running in single-threaded mode.
Please report an issue on GitHub to help us make nvm run faster on your computer!

<details>
<!-- do not delete the following blank line -->

```sh
Local cache found: ${NVM_DIR}/.cache/src/node-v12.16.2/node-v12.16.2.tar.xz
Checksums match! Using existing downloaded archive ${NVM_DIR}/.cache/src/node-v12.16.2/node-v12.16.2.tar.xz
$>./configure --prefix=/c/Users/diama/.nvm/versions/node/v12.16.2 <
which: no python2.7 in (/c/Users/diama/bin:/mingw64/bin:/usr/local/bin:/usr/bin:/bin:/cmd:/c/ProgramData/Oracle/Java/javapath:/c/Program Files (x86)/Intel/iCLS Client:/c/Program Files/Intel/iCLS Client:/c/WINDOWS/system32:/c/WINDOWS:/c/WINDOWS/System32/Wbem:/c/WINDOWS/System32/WindowsPowerShell/v1.0:/c/Program Files (x86)/Intel/Intel(R) Management Engine Components/DAL:/c/Program Files/Intel/Intel(R) Management Engine Components/DAL:/c/Program Files (x86)/Intel/Intel(R) Management Engine Components/IPT:/c/Program Files/Intel/Intel(R) Management Engine Components/IPT:/c/WINDOWS/System32/OpenSSH:/c/Program Files/Intel/WiFi/bin:/c/Program Files/Common Files/Intel/WirelessCommon:/cmd:/c/Program Files/Java/jdk1.8.0_101/bin:/c/Program Files/nodejs:/c/Users/diama/AppData/Local/Microsoft/WindowsApps:/c/Users/diama/AppData/Local/atom/bin:/c/Users/diama/AppData/Local/Microsoft/WindowsApps:/c/Users/diama/AppData/Local/hyper/app-3.0.2/resources/bin:/c/Users/diama/AppData/Local/Programs/Microsoft VS Code/bin:/c/Users/diama/AppData/Roaming/npm:/usr/bin/vendor_perl:/usr/bin/core_perl)
which: no python2 in (/c/Users/diama/bin:/mingw64/bin:/usr/local/bin:/usr/bin:/bin:/cmd:/c/ProgramData/Oracle/Java/javapath:/c/Program Files (x86)/Intel/iCLS Client:/c/Program Files/Intel/iCLS Client:/c/WINDOWS/system32:/c/WINDOWS:/c/WINDOWS/System32/Wbem:/c/WINDOWS/System32/WindowsPowerShell/v1.0:/c/Program Files (x86)/Intel/Intel(R) Management Engine Components/DAL:/c/Program Files/Intel/Intel(R) Management Engine Components/DAL:/c/Program Files (x86)/Intel/Intel(R) Management Engine Components/IPT:/c/Program Files/Intel/Intel(R) Management Engine Components/IPT:/c/WINDOWS/System32/OpenSSH:/c/Program Files/Intel/WiFi/bin:/c/Program Files/Common Files/Intel/WirelessCommon:/cmd:/c/Program Files/Java/jdk1.8.0_101/bin:/c/Program Files/nodejs:/c/Users/diama/AppData/Local/Microsoft/WindowsApps:/c/Users/diama/AppData/Local/atom/bin:/c/Users/diama/AppData/Local/Microsoft/WindowsApps:/c/Users/diama/AppData/Local/hyper/app-3.0.2/resources/bin:/c/Users/diama/AppData/Local/Programs/Microsoft VS Code/bin:/c/Users/diama/AppData/Roaming/npm:/usr/bin/vendor_perl:/usr/bin/core_perl)
./configure: line 3: /c/Users/diama/AppData/Local/Microsoft/WindowsApps/python: Permission denied
./configure: line 3: /c/Users/diama/AppData/Local/Microsoft/WindowsApps/python: Permission denied
nvm: install v12.16.2 failed!
```sh
</details>

#### What did you expect to happen?
Downgrade the version

#### Is there anything in any of your profile files that modifies the `PATH`?
<!--  (e.g. `.bashrc`, `.bash_profile`, `.zshrc`, etc) -->
I don't think so