Angular 4错误：有多个模块的名称只有外壳不同

./src/app/Utils/config.service.ts
There are multiple modules with names that only differ in casing.
This can lead to unexpected behavior when compiling on a filesystem with other case-semantic.
Use equal casing. Compare these module identifiers:
* D:ANGULARsiteprice.orgnode_modules@ngtoolswebpacksrcindex.js!D:ANGULARsiteprice.orgsrcappUtilsconfig.service.ts
Used by 1 module(s),i. e.
D:ANGULARsiteprice.orgnode_modules@ngtoolswebpacksrcindex.js!D:ANGULARsiteprice.orgsrcapputilsemail.service.ts
* D:ANGULARsiteprice.orgnode_modules@ngtoolswebpacksrcindex.js!D:ANGULARsiteprice.orgsrcapputilsconfig.service.ts
Used by 2 module(s),i. e.
D:ANGULARsiteprice.orgnode_modules@ngtoolswebpacksrcindex.js!D:ANGULARsiteprice.orgsrcappapp.module.ts

config.service.ts文件：

import { Injectable } from '@angular/core';

@Injectable()
export class ConfigService {

  _apiURI : string;

  constructor() {
      this._apiURI = 'http://www.example.com/xyz/api/';
    }

    getApiURI() {
        return this._apiURI;
    }

    getApiHost() {
        return this._apiURI.replace('api/','');
    }

}

email.service.ts：

import { Injectable } from '@angular/core';
import { Http,Response,Headers } from '@angular/http';
import {Observable} from 'rxjs';
import 'rxjs/add/operator/map';
import { ConfigService } from '../Utils/config.service';
import { Email } from '../Models/email';

@Injectable()
export class EmailService {

  apiRoot: string = '';

  constructor(private http: Http,private configService: ConfigService) { 
    this.apiRoot = configService.getApiURI();
  }

我检查了服务名称的大小写,它们是正确的.