after downloading node using nvm, the error message program is occupied and the node_modules folder is empty

C:\Users\Administrator>nvm uninstall 8.12.0
Uninstalling node v8.12.0... done
C:\Users\Administrator>nvm install 8.12.0
Downloading node.js version 8.12.0 (64-bit)...
Complete
Downloading npm version 6.4.1... Download failed. Rolling Back.
Rollback failed. remove C:\dev\nvm\temp\npm-v6.4.1.zip: The process cannot access the file because it is being used by another process.
Could not download npm for node v8.12.0.
Please visit https://github.com/npm/cli/releases/tag/v6.4.1 to download npm.
It should be extracted to C:\dev\nvm\v8.12.0

there is no npm command in the folder

the image address has also been changed

root: C:\dev\nvm
path: C:\dev
arch: 64
proxy: none
node_mirror: http://npm.taobao.org/mirrors/node/
npm_mirror: http://npm.taobao.org/mirrors/npm/

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