Windows10中Yarn 1.5.1经npm卸载后仍无法升级该如何解决？

安全阿岳

2026-7-20

解决Windows 10下npm卸载Yarn后无法升级的问题

问题场景

Windows 10系统，当前Yarn版本为1.5.1，执行npm uninstall -g yarn后尝试升级Yarn，出现连接错误与空值读取错误。

执行命令及输出

卸载Yarn命令

npm uninstall -g yarn

输出：

removed 1 package, and audited 1 package in 18s

found 0 vulnerabilities

升级Yarn命令

npm upgrade --global yarn

输出：

npm notice Beginning October 4, 2021, all connections to the npm registry - including for package installation - must use TLS 1.2 or higher. You are currently using plaintext http to connect. Please visit the GitHub blog for more information: https://github.blog/2021-08-23-npm-registry-deprecating-tls-1-0-tls-1-1/
npm notice Beginning October 4, 2021, all connections to the npm registry - including for package installation - must use TLS 1.2 or higher. You are currently using plaintext http to connect. Please visit the GitHub blog for more information: https://github.blog/2021-08-23-npm-registry-deprecating-tls-1-0-tls-1-1/
npm ERR! Cannot read properties of null (reading 'pickAlgorithm')

npm ERR! A complete log of this run can be found in:
npm ERR!     C:\Users\qxz3xng\AppData\Local\npm-cache\_logs\2023-06-02T05_54_25_455Z-debug-0.log

问题分析

当前npm使用明文HTTP连接访问注册表，不符合要求的TLS 1.2及以上版本规范，导致连接受限
连接异常引发npm无法正常获取包信息，进而出现Cannot read properties of null (reading 'pickAlgorithm')错误

解决步骤

切换npm注册表为HTTPS源
```
npm config set registry https://registry.npmjs.org/
```
执行以下命令验证设置：
```
npm config get registry
```
确认输出为https://registry.npmjs.org/即可。
清理npm缓存
```
npm cache clean --force
```
彻底清理残留的Yarn文件（若卸载后仍能查到版本）
1. 删除全局Yarn模块目录：C:\Users\[你的用户名]\AppData\Roaming\npm\node_modules\yarn
2. 删除Yarn可执行文件：C:\Users\[你的用户名]\AppData\Roaming\npm\yarn.cmd和yarnps.cmd
重新安装最新版Yarn
```
npm install -g yarn
```
验证安装结果
```
yarn --version
```
确认输出为最新版本即完成修复。