ERROR in: Illegal state: Could not load the summary for directive RouterOutlet in path//node_modules/@angular/router/router.d.ts

When wanting to do an "ng build --prod", this error jumps:

ERROR in: Illegal state: Could not load the summary for directive RouterOutlet in path//node_modules/@angular/router/router.d.ts

From what I saw it related to @ angular-devkit / build-optimizer.

If I run "ng build --prod --aot false --build-optimizer false" the buid is done but it seems that it does not perform a good optimization.

Why should I miss this error when doing "ng build --prod"?

tsconfig.json

{
  "compilerOptions": {
    "baseUrl": "",
    "declaration": false,
    "emitDecoratorMetadata": true,
    "experimentalDecorators": true,
    "lib": ["es6", "dom"],
    "mapRoot": "./",
    "module": "es6",
    "moduleResolution": "node",
    "outDir": "../dist/",
    "sourceMap": true,
    "target": "es5",
    "typeRoots": [
      "../node_modules/@types"
    ],
    "noEmitOnError": true
  }
}

package.json

{
"name": "app",
"version": "1.6.1",
"description": "app",
"author": "",
"url": "",
"copyright": "Copyright 2017 app",
"license": "",
"angular-cli": {},
"scripts": {
  "start": "ng serve --o",
  "lint": "tslint \"src/**/*.ts\"",
  "test": "ng test",
  "pree2e": "webdriver-manager update",
  "e2e": "protractor"
},
"private": true,
"dependencies": {
  "@angular/animations": "^5.2.1",
  "@angular/common": "^5.2.1",
  "@angular/compiler": "^5.2.1",
  "@angular/core": "^5.2.1",
  "@angular/forms": "^5.2.1",
  "@angular/http": "^5.2.1",
  "@angular/platform-browser": "^5.2.1",
  "@angular/platform-browser-dynamic": "^5.2.1",
  "@angular/platform-server": "^5.2.1",
  "@angular/router": "^5.2.1",
  "@angular/upgrade": "^5.2.1",
  "angular2-ladda": "^1.2.3",
  "angular2-text-mask": "^8.0.4",
  "bootstrap": "^4.0.0-beta.2",
  "core-js": "^2.5.3",
  "font-awesome": "^4.7.0",
  "hashmap": "^2.3.0",
  "jquery": "^3.3.1",
  "moment": "^2.20.1",
  "ngx-bootstrap": "^2.0.3",
  "node-sass": "^4.7.2",
  "popper.js": "^1.12.9",
  "primeng": "^5.2.4",
  "rxjs": "5.5.6",
  "simple-line-icons": "^2.4.1",
  "text-mask-addons": "^3.7.1",
  "ts-helpers": "^1.1.2",
  "zone.js": "^0.8.20"
},
"devDependencies": {
  "@angular-devkit/build-optimizer": "^0.6.0",
  "@angular/cli": "^1.7.4",
  "@angular/compiler-cli": "^5.2.1",
  "@types/jasmine": "~2.8.4",
  "@types/jasminewd2": "~2.0.2",
  "@types/lodash": "^4.14.93",
  "codelyzer": "4.1.0",
  "jasmine-core": "~2.9.1",
  "jasmine-spec-reporter": "~4.2.1",
  "karma": "2.0.0",
  "karma-chrome-launcher": "^2.2.0",
  "karma-jasmine": "^1.1.1",
  "karma-remap-istanbul": "^0.6.0",
  "protractor": "5.2.2",
  "ts-node": "4.1.0",
  "tslint": "5.9.1",
  "typescript": "^2.6.2"
}
}

More data

npm version: 5.8.0
Angular CLI: 1.7.4
Node: 6.9.1
OS: win32 x64
Angular: 5.2.1

I've been with this error for hours, I'd appreciate it if you can help me with this.

Thanks !!!