我的电脑出现问题，我将 Windows 恢复到旧的恢复点。

在此之后...当我尝试构建我的 Angular 应用程序时，我遇到了下一个错误：

C:\Udemy\AngularDeCeroAExpertoEdicion2021\03-paisesApp>npm run build

> paises-app@0.0.0 build C:\Udemy\AngularDeCeroAExpertoEdicion2021\03-paisesApp
> npm run config -- --environment=prod && ng build --prod


> paises-app@0.0.0 config C:\Udemy\AngularDeCeroAExpertoEdicion2021\03-paisesApp
> ts-node ./src/assets/scripts/setEnv.ts "--environment=prod"

internal/modules/cjs/loader.js:329
      throw err;
      ^

Error: Cannot find module 'C:\Udemy\AngularDeCeroAExpertoEdicion2021\03-paisesApp\node_modules\typescript\lib\typescript.js'. Please verify that the package.json has a valid "main" entry
    at tryPackage (internal/modules/cjs/loader.js:321:19)
    at Function.Module._findPath (internal/modules/cjs/loader.js:534:18)
    at Function.Module._resolveFilename (internal/modules/cjs/loader.js:888:27)
    at Function.resolve (internal/modules/cjs/helpers.js:98:19)
    at loadCompiler (C:\Users\myuser\AppData\Roaming\npm\node_modules\ts-node\dist\index.js:208:34)
    at create (C:\Users\myuser\AppData\Roaming\npm\node_modules\ts-node\dist\index.js:213:28)
    at Object.register (C:\Users\myuser\AppData\Roaming\npm\node_modules\ts-node\dist\index.js:184:21)
    at main (C:\Users\myuser\AppData\Roaming\npm\node_modules\ts-node\dist\bin.js:129:29)
    at Object.<anonymous> (C:\Users\myuser\AppData\Roaming\npm\node_modules\ts-node\dist\bin.js:448:5)
    at Module._compile (internal/modules/cjs/loader.js:1085:14) {
  code: 'MODULE_NOT_FOUND',path: 'C:\\Udemy\\AngularDeCeroAExpertoEdicion2021\\03-paisesApp\\node_modules\\typescript\\package.json',requestPath: 'typescript'
}
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! paises-app@0.0.0 config: `ts-node ./src/assets/scripts/setEnv.ts "--environment=prod"`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the paises-app@0.0.0 config script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     C:\Users\myuser\AppData\Roaming\npm-cache\_logs\2021-08-01T08_27_09_159Z-debug.log
npm ERR! code ELIFECYCLE
npm ERR! errno 1
npm ERR! paises-app@0.0.0 build: `npm run config -- --environment=prod && ng build --prod`
npm ERR! Exit status 1
npm ERR!
npm ERR! Failed at the paises-app@0.0.0 build script.
npm ERR! This is probably not a problem with npm. There is likely additional logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     C:\Users\myuser\AppData\Roaming\npm-cache\_logs\2021-08-01T08_27_09_186Z-debug.log

我认为问题出在目录上：

C:\Users\myuser\AppData\Roaming\npm\node_modules\

我能做什么？ 删除文件夹 node_modules？ 重新安装 npm？

我尝试了 npm install，一切正常。

谢谢。

已编辑：

也许问题出在我合并的分支或类似的地方。